Los Angeles Cactus and Succulent Society
Los Angeles Cactus and Succulent Society
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Didiereaceae - September 2015
The Didiereaceae (pronounced Dee-dee-air-ee-ace-ee-ee) was long thought to be an exclusively Madagascan family consisting of four genera and about 11 species, all thorny scrub shrubs and trees with drought deciduous leaves. All are pretty easy to recognize as related to each other, and with all of them being on Madagascar it made for a tidy story about evolution on the island. Then came those darn taxonomists using DNA to look at the actual relationships of Didiereaceae and its close relatives, the Cactaceae and Portulacaceae (plus some other families you probably don't know).
While the DNA phylogeny did confirm what we already knew, that the four genera of Didiereaceae (Alluaudia, Alluaudiopsis, Didierea, and Decarya) are very closely related, it also surprised us by showing the South African genera Portulacaria and Ceraria are also closely related and belong in the family. In addition there is an enigmatic East African genus, Calyptrotheca which contains one or two species. For the sake of the monthly show note that I have listed every genus in the family above.
Let's start with the traditional, Madagascar group. All the species are found in the dry scrub forests of Madagascar where thorny shrubs and trees which drop their leaves in the dry season dominate. They fit right in as all of them are thorny shrubs and trees that drop their succulent leaves during times of drought. Alluaudia is the largest genus with six species and has some of the most unusual species. Alluaudia procera forms huge (20 feet and taller) individual, usually unbranched stems) arising from ground level up to a few feet off the ground. Decarya, with one species, is a many branched shrub distinctive for its zig-zag branches.
The continental African branch of the family was a surprise to many at first as Ceraria and Portulacaria are thornless and more succulent. But what I see are shrubs (except the tiny C. pygmaea) that are semi-woody and in the case of Ceraria drop their leaves readily in drought only to regrow them as soon as the rains come, just like the Madagascar plants. Portulacaria may retain its leaves but has a similar growth habit. Finally, there is Calyptrotheca. There is virtually no information about this genus that I can find on the internet, except that it is a 10-15 foot shrub with stems up to a foot thick. It sounds like a pachyform but the only image on the internet is of small tip branches with flowers but no leaves. It would be interesting to see this genus brought into cultivation!
Portulacaria is far and away the most widely planted species in our region. It is so easy that it is used commonly in drought tolerant landscapes for people who know nothing about plants. A distant second is A. procera which can often be seen for sale at regular nurseries. All the other species are usually seen only in specialist collections. The biggest problem in growing them is sensitivity to frost (particularly for the Madagascar plants) though many in our region grow these species successfully.
Photos in Cactus Chronicle:
Ceraria namaquensis, zig zag stems of Decarya, Didierea madagascariensis
-- Kyle Williams
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Dischidia - September 2007
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Discocactus - March 2018, January 2015
Discocactus are heavily ribbed South American cacti, primarily from Brazil. The genus is quite old, first described in 1837. The name comes from the shape of the body, which tends to be much flatter than tall, at least compared to the other ball like genera (Parodias etc.) that share its habitat. Discocactus can be found inland in the state of Minas Gerais, and further South in the states of Sao Paulo, Parana, Mato Grosso, and crossing into Paraguay, and even into the Southeastern most state of Bolivia, Santa Cruz.
Although popular in cultivation, many of the species are endangered in the wild.
The beautiful spination, the flat bodies, and the pleasantly fragranced flowers have made this a popular genus, and there are far more names in cultivation than there are true species. The number of species has varied from more than 60 down to 24 in recent publications (1990s), to the currently recognized 7. This is unlikely to be the last word on this attractive genus, so keep your old labels, they may soon be good again. In our shows, most of the generic names are accepted.
The distinguishing characteristics of Discocactus are globular to flattened globular shape, a cephalium, and fragrant night blooming flowers. The cephalia stay relatively small, are almost always white, and have long soft wool. Discocactus have ring-meristems (a ring of growth cells) that surround the cephalium, and allow the body to continue to grow after the cephalium forms. This growth ring distinguishes Discocactus from the very similar and related Melocactus.
Discocactus has similar cultivation requirements to other tropical terrestrial cacti such as Melocactus and Uebelmannia. They thrive in warm humid climates where even the nights stay quite warm. However, they are fine in our Mediterranean climate with cool summer nights so long as we give them some extra warmth in the winter months. They shouldn't be kept in a location where the temperature drops below about 50F. They like more moisture than similar looking non-tropical cacti, but don't keep them wet, especially in the winter.
Photos in Cactus Chronicle --
Discocactus buenekeri, Discocactus araneispinus, Variegated Discocactus
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Dorstenia - September 2013, August 2009
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Dudleya - February 2011, October 2007
Dudleyas are a succulent plant found throughout southwest U.S. and Mexico. They have a fleshy glaucous leaf structure which is easy to spot as you drive on Southern California highways and freeways.
Dudleyas can be grown in full sun almost anywhere in the Los Angeles area and tend to be winter grower. They form rosettes at the end of stems that may contain as many as 100 leaves. Flower are produced in late to early winter and are formed on long stalks that can reach up to three feet in length.
Photo in Cactus Chronicle:
Dudleya brittonii
Sajeva and M. Costanzo, Succulents, The Illustrated Dictionary.
Tom Glavitch, 2003 - Edited by Steve Frieze, 2011
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Dyckia & hybrids - October 2009
Dyckias, are generally one of the most cold hardy of all of the Bromeliad genera. While most people are scurrying around trying to bring in the last of their plants before the first blue norther hits, Dyckia growers can sit back and enjoy themselves knowing that most of their plants can take temperatures down into the low twenties, or even the upper teens. Those Dyckias are tough plants!
Dyckia is one of the genera in the subfamily Pitcairnioideae. This subfamily contains some of the most primitive Bromeliad species. Most Pitcairnioideae genera are saxicolous (living on or around rocks) or terrestrial (growing in the ground), with Dyckias into both categories (e.g. D. saxicola), although most are strictly terrestrial and all do well when grown as strict terrestrials. The majority of the approximately 120 different species of Dyckia are native to central Brazil, with some being found in Uruguay, Paraguay, Argentina, and Bolivia. Most are found growing among rocks in warm sunny areas ranging in altitude from sea level to 2000 meters.
The genus was introduced into Europe during the nineteenth century, and was named for Prince von Salm-Dyck, an early expert on succulents. Although Dyckias have no internal water storage tissue like true succulents, they are xerographic and survive long periods without water by going dormant. Their rosette of thick succulent leaves will eventually wilt, but recovery is rapid when watering is resumed. These plants are tough! They will withstand more neglect than almost any other commonly cultivated plant and still pup and bloom every year. Their only demand is a little water and a lot of sunshine. In the spring they bear multiple red, yellow or orange flowers on a thin stalk that emerges from the side of the plant. The stalk length can range from about 10 centimeters for a small species like D. choristaminea to more than 2 meters for D. maritima.
Although the flowers aren’t large, bees, wasps and hummingbirds find them attractive. The plants themselves come in a range of colors (green, rose, maroon, tan, or silver), and a variety of leaf shapes (long and thin, short and fat, deeply lobed, or almost smooth). In an outdoor setting with considerable sunshine, these plants may be a welcome addition to your garden.
-- from the Bromeliad Society of Houston, Texas
{October 2009 Cactus Chronicle not present in archives}
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C
Cacti from Coahuila - October 2013
Located in the central part of Northern Mexico the state of Coahuila shares its borders with the once Mexican land of Texas in the U.S. along the Rio Bravo or Rio Grande to the north, and with the states if Nuevo Leon to the east, Zacatecas to the south, Durango to the southwest and Chihuahua to the west.
Its vast area of 151,595 square kilometers makes it the third largest Mexican state in terms of territory, only behind Chihuahua and Sonora. Coahuila is located within the Chihuahuan Desert. Also standing out as part of the state's physical features are the Mapimi Desert, and the fertile lands of the so-called Lagunera region shared with the neighboring state of Durango.
The hydrological zone of the Rio Bravo-RioConchos lies within the state's limits. The Rio Bravo is the northern frontier and flows into the Gulf of Mexico as well as the basin of the Nazas River-Aguanaval River, another major hydrological system within the region. Some other rivers are born in the local mountain chains, including the Alamos and others.
Local climate usually includes dry or semi-dry conditions, along with disturbingly high temperatures across the lowlands (some areas of Coahuila can reach high temperatures of 120 to 125F) while the pine and oak forests produce fresher and more moderate conditions along the eastern Sierra Madre. The rest of the territory is home to typical desert scrubland, containing wild lettuce, cassava and thistle bushes.
About 12,000 years ago, nomadic hunters entered this region, which once included South Texas. Archeological evidence suggests early hunter-gatherer cultures evolved into fixed societies that engaged in agriculture and fishing and used area caves as shelter. Later, Coahuila became home to several Indian tribes. When the Spaniards arrived, they found the natives to be peaceful and prosperous. Sadly, nearly 90% of the indigenous population was killed by European diseases.
The Spanish colonized the state between 1550 and 1580. Colonization was impeded by the vast desert, extreme weather and shortage of water. The state of Texas was part of the Mexican State, Coahuila y Tejes before declaring independence in 1835.
Partial list of cactus genera and species native to Coahuila:
Ariocarpus fissuratus, Astrophytum capricorne, A. cohuilerae, Coryphantha, Echinocereus, Echinomastus, Gymnocactus, Lophophora, Mammillaria, Opuntia, Stenocactus, Thelocactus, Turbinicarpus.
-- Manny Rivera
Edited by Kyle Williams
Photos in Cactus Chronicle:
Ariocarpus, Astrophytum, Stenocactus
{original very blurry and difficult to decipher,
some species and place names unreadable and not included}i
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Calibanus - April 2014, September 2008
caudiciform - September 2007
This group used to be called, the plant family Agavaceae, but today are considered part of the Asparagus family Asparagaceae. Cultivation of most species is easy. Nearly all can grow in the ground, and most, but the largest species, can live happily in pots. They are mainly warm season growers so provide some water during the spring through fall to get them to look their best.
Calibanus is unusual. At first glance, you might think you are looking at a big tuft of blue-green grass, but upon closer inspection you will see the large, fissured, woody caudex that makes this plant so desirable. It makes a nice specimen either in the ground or in a pot. I recommend raising the base to show off the caudex to its greatest extent.
-- Kyle Williams
Photo in Cactus Chronicle:
Calabanus hookerii
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Caralluma - September 2009 & 2008
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Caudex succulents of Baja - March 2009
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Cephalium bearing cacti - June 2012
Melocactus are immediately recognizable by the large cephalium that develops on mature plants. Melocactus grow as normal appearing, but flowerless, globular cacti until they reach maturity. This can take from 6 to 15 years in cultivation, with a greater range in habitat. Once they reach maturity, the body stops growing vigorously (it still grows slowly). Most of the plant energy goes into producing a cylindrical flowering and fruiting structure known as a cephalium. This is usually white, with short hairs of yellow, orange or red. As the years go by, the cephalium becomes more cylindrical, with the base becoming more colorful The flowers are usually a red-purple, and the fruits are almost always a bright red, to attract birds. With age, the cephalium can grow to 18 inches or more in height, occasionally bifurcating or trifurcating.
Endemic to Southern Brazil, Discocactus are prized by the collector if for no other reason that the elegant wooly cephalium the plants develop in maturity. Similar to Melocactus, flowers develop from the cephalium, which can reach two or more inches in height.
Photos in Cactus Chronicle:
Discocactus psuedoinsignis in a sandy habitat, Discocactus buenekeri,
Discocactus horstii, Melocactus azureus,
Melocactus azureus entered by Rosemarie Sauer in the 2003 CSSA Show
Reference:
D. Hunt, The New Cactus Lexicon
The Brazilian Cactus Project (web), Marlon Machado
Tom Glavich April 2004 -- Steve Frieze, June 2012
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Ceraria - January 2015
Ceraria is a genus of Southern African (primarily South African and Namibia) succulents that is interesting both from a horticultural perspective and a taxonomic one.
Ceraria is not commonly grown. It has just a few species, primarily in Namibia. The genus is similar to, and related to, Portulacaria. They form woody shrubs to small trees with peeling bark. The leaves small and fleshy, and drop off in times of drought. Ceraria pygmaea is the smallest species and can make a nice succulent bonsai.
Ceraria traditionally belonged to the Purslane Family, Portulacaceae. However, modern taxonomic research use DNA has discovered that it doesn't belong in that family. Ceraria has now, along with Portulacaria, been placed in the Didiereaceae. Prior to this all Didiereaceae were thought to be thorny shrubs from Madagascar (e.g. Didierea and Allauaudia). Now this extends the family to the African mainland. Another finding from molecular research is that Anacampseros and Avonia are really the same genus (to be called Anacampseros) and belong in their own separate family, the Anacamserotaceae. It would be difficult to call this a completely new finding as taxonomists originally considered them the same genus before splitting them up.
-- Kyle Williams
Photo in Cactus Chronicle:
Ceraria namaquensis
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Ceriods (North America) - September 2015
Ceroids are the group of cacti that used to pretty much all be lumped into Cereus by early taxonomists. Allowing for a few exceptions, this group encompasses all the columnar cacti. This is NOT a natural or "monophyletic" group of genera despite once being thought to be so. DNA research has shown that, for example, Cereus is more closely related to Gymnocalycium than it is to Pachycereus! For the sake of discussion consider any genus with "-cereus" in the name (e.g. Pachycereus, Selenocereus, Acanthocereus, etc.) to be a Cereoid cactus. Also add in most any cactus that has columnar growth similar to these species, such as Carnegeia, Espostoa, or Harrisia. Keep in mind that a cactus does not have to be upright to be columnar. For example, some Echinopsis have a long trailing habit. Just to be clear, columnar growth means the stems normally are round in cross section and grow long and unjointed (i.e. not Opuntia), nor is the shrubby Pereskia part of this group.
While most any cactus can be grown in a pot, most Cereoids are at their best as landscape specimens allowed to reach their full potential. Echinopsis panchoi (San Pedro) may be one of the most commonly grown cacti in our region, but it is hard not to be impressed whenever you see a well grown tree like specimen 20' or taller with dozens upon dozens of stems! A bright blue Pilocereus is a focal point in any succulent landscape. And let's not forget the majesty of a mature Saguaro (Carnegia gigantea), despite it doing poorly in our region. Stenocereus eruca is an interesting Cereoid from Arizona that is, by any definition, a large columnar cactus with stems 10' or longer, but you'll never see it looking across the horizon as it grows flat on the ground (prostrate). It takes a lot of space in a landscape because of this habit, but if you have the room and don't mind all the spines it really is a conversation piece! There are also plenty of smaller species that can make excellent potted specimens such as small Echinopsis, Pygmaeocereus, or smaller species of Espostoa.
Cereoids make up a huge group of cacti, representing well over half the family. North American examples include genera such as Pachycereus, Peniocereus, Echinocereus, and Stenocereus.
-- Kyle Williams
Photos in Cactus Chronicle:
Saguaro, Stenocereus eruca,
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Cissus - September 2016, July 2010
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Columnar Cacti - February 2014
Columnar cacti are a highly heterogeneous group defined by growth form rather than any natural grouping or relationship. As such, there is very little that unifies the group outside of growth form, which can roughly be defined as an upright, mostly self supporting, cactus that is at least twice as tall as wide. Implied in this definition is that the "column" is largely unjointed, thereby excluding cacti such as Opuntia and Schlumbergera. Even so, we are left with a vast array of cacti that are anywhere from a few inches to over 50 feet tall, ranging from the United States all the way down to southern South America, with cold tolerance ranging from highly frost sensitive to those that can be frozen solid for the winter without harm. To add confusion to the mix, some species start out as globular but after many years become columnar. For example, Astrophytum species are usually seen in shows as globular, or short columnar plants at most. However, at the Huntington Garden you can see examples of Astrophytums in the ground that are several feet tall!
So what can we say about them? As a rule, they tend to grow faster than globular cacti. They also are more tolerant of full sun, as the nature of their growth means they don't stay shaded by shrubs and grasses unlike their more diminutive counterparts. Larger species will eventually need to be put in the ground. Smaller types (like many Mammillaria) make wonderful specimen plants in pots for years on end. Some of the taller types may require some staking in windy climates to avoid the risk of snapping in a wind-storm. When choosing a place to plant them it is important to know if the cactus stays fairly upright and unbranched or if it sends out multiple stems and branches turning into a giant shrub of sorts. Knowledge of growth rate is also key, as many species can reach 15 feet in a few years, while a Saguaro may take your entire lifetime to reach that height! With such variation between species it is paramount that you look up the specific requirements of the plants you choose.
-Kyle Williams
Photos in Cactus Chronicle:
Astrophytum ornatum “columnar”, Espostoa melanostele, Astrophytum ornatum “globular”,
Carnegiea gigantea, Stenocereus eruca, Mammillaria bombycina
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Commiphora - August 2013 & 2019
Both Bursera and Commiphora are members of the Burseraceae. Commiphora are confined to the Old World, mostly South and East Africa and Madagascar.
. . . some of the Commiphora are more sensitive to freezing temperatures, and need protection when freezes occur.
Commiphora is a widespread genus, stretching from South Africa through tropical Africa and continuing into Madagascar. Many of the species have peeling bark, although the color tends to run more towards the yellow and brown rather than red.
Commiphora capensis and cervifolia are both occasionally available. Unnamed (or unidentified) species of Commiphora from Sudan, Madagascar, Kenya, and Tropical Africa are sometimes available, and beginning to be propagated. Named species are beginning to appear on seed lists and nursery catalogs. The genus is understudied, and there are many species unknown or unidentified.
Vigorous growth is also found in well fed and watered plants. Commiphora are aromatic, with fragrances that manage to be both similar and different to Bursera. Commiphora pyracanthoides is similar to some of the tall growing Bursera, and is easily grown from seed.
Photo in Cactus Chronicle:
Commiphora orbicularis
-- Kyle Williams, Special Thanks to Tom Glavich
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Conophytum - March 2016, February 2013, October 2006
Conophytum's reputation for being touchy and difficult to grow is undeserved. While they are usually grown in pots on benches, they can be a part of rock garden landscapes, as seen at the Sherman Library & Gardens in Corona del Mar.
Many people seeing Conophytum for the first time assume they must be some type of Lithops, so great is the similarity. Both genera do have the "living stones" look to them, belong to the same family, the Aizoaceae (often informally called Mesembs), and are native to South Africa and Namibia. However, a closer look will allow you to tell them apart quite easily. The best way
to identify a Conophytum is to look at the leaves. In Lithops you have two distinct leaves, while in Conophytum the leaves are fused together with just a small pore or slit in the center from which the flowers emerge. Conophytum forms a dry papery sheath around itself when dormant while Lithops never does. Another clue is that Conophytum are winter growers while Lithops are most active in summer and fall. This feature is an adaptation to the areas they grow in the wild; Lithops in summer rainfall regions and Conophytum in winter rainfall zones. Additionally, Conophytum flowers have petals united into a tube at the base and "bracts" (small scale or leaf like growths) on the tube. Lithops has no tube or bracts.
Cultivation of most species of Conophytum is fairly straightforward. As the weather cools in the fall start watering your plant. If it is ready to grow it will suck up water and burst forth from the protective sheaths. Water regularly during the growing season as the plants should not dry out during this time, though keeping them too wet risks bloating, splitting and rot. A very fast draining planting medium is recommended. Keep an eye out for signs of the leaves shrinking and collapsing when the days get warmer and longer in the spring. This is perfectly normal and you should stop watering at this time. The plants will shrink down quite a bit as the leaves turn into a dry, papery sheath that will protect the next year's leaves until fall. From this point until the fall the plants are in dormancy. Smaller species may need a bit of water, the bigger ones likely won't need any. Plants like some sun in growing season, but once the plants start entering dormancy move them to a shady location to avoid scorching. Some species can withstand light frost, but it is best to protect your plants if frost threatens. Commonly available species include C. bilobum, C. obcordellum, and C. uviforme.
-- Kyle Williams
Photos in Cactus Chronicle:
Conophytum wettstenii showing papery sheaths, Conophytum “Shokkoden”, Conophytum obcordellum
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Copiapoa - January 2017, March 2013, March 2010, October 2007
Copiapoa is a genus of spectacular cacti from the Atacama Desert along the north coast of Chile. Copiapoa were first collected in the 1840s, and described as Echinocactus, then the home to any of the more or less globular cacti. The genus Copiapoa was named by Britton and Rose in 1922 in their great work The Cactaceae. The name derives from Chilean province of Copiapo, home of many of the species. Currently 26 species of Copiapoa are generally recognized. Species of this genus are relatively small, though they can form large clumps. The largest species rarely surpass three feet in height, while the smallest species, C. laui, rivals Blossfeldia for the title of world's smallest cactus.
The habitat of Copiapoa is incredibly dry, even by desert standards. They occur in the Atacama, the world's driest desert. The average rainfall in the region is 1mm/year (0.04 inches). Many areas get rainfall only once every four years and some weather stations have never recorded a single drop of rain! Interestingly Copiapoa thrives in these extreme conditions to the extent that the genus peters out at the northern and southern ends of its range because these areas are where rainfall starts to become more regular and predictable.
How can any plant, even a cactus, survive in a climate where years can go by without rain? They do it by living off the fog that regularly covers the coastal regions of northern Chile. Anyone living in coastal California in June knows this gloomy fog all too well. Surely we've all noticed our plants, and pretty much any outside surface, covered in moisture condensed from the fog on overcast mornings. Without this fog, even Copiapoa could not survive in the Atacama Desert.
Copiapoa live along the coast and through the river valleys cut through the coastal mountains. The hills and valleys of Northern Chile are still not well explored from a botanical point of view. When these areas have been explored new species have been found, and it is likely more will found in the future.
Given these extremely dry conditions, one would expect cultivation to be difficult in our comparatively wet Southern California winters. Fortunately, this is not so, and Copiapoa are relatively easy to grow. They respond happily to the same potting mix, watering, and fertilization as most cacti. When given favorable growing conditions these plants develop many times faster than they would in their native habitat. Some species can even be grown in the open ground in the Los Angeles area, as long as the soil is well drained. They do tend to grow slower than some other cacti of similar size.
Copiapoa are easily propagated from cuttings or division of clumps. Seed is available from the CSSA seed bank, and most cactus seed nurseries. These seeds germinate quickly in the spring. They should be started in a moist potting mix, and moved to drier media after germination. They do very well in a mineral potting mix with almost no organic matter.
-- Kyle Williams
Photos in Cactus Chronicle:
Copiapoa coquimana in habitat, two more photos with no captions.
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Coryphantha - February 2023, February 2018, July 2014, March 2008 & 2007
Coryphantha and Escobaria are two moderate sized genera (57 and 23 species respectively) of small North American cacti similar in appearance to Mammillaria and were originally included in
that genus. They share in common a small, mostly globular, stature and an incredible level of cold tolerance, at least in some species. Escobaria vivipara and E. missouriensis are particularly widespread species covering most of western and midwestern North America. In fact, the native range of E. vivipara extends all the way into Canada, a feat matched only by a few species of Opuntia. This cold tolerance allows people in even the coldest climates to grow these species outdoors.
While all plants in this group are relatively small, many can form good sized clumps in time (much like Mammillaria). Some of the variation between species include having globular plants and more cylindrical, upright plants. Flowers vary from yellow to pink. Some species are covered in dense white spines while others are more sparesly covered, allowing the green body of the plant to shine through. A large number of species produce tap roots. Cultivation is similar to Mammillaria and other small cacti. While some members of these genera are renowned for their cold tolerance, keep in mind many species come from warm climates. Of course that isn't much of an issue for us in California, but anyone growing them in cold climates needs to make sure they pick the cold tolerant species.
Coryphantha and Escobaria are two closely related genera that are in turn closely related to Mammillaria. In fact many botanists feel that Escobaria should not be recognized as a genus, instead lumping all the species in Coryphantha itself. This is what the authors of "The Flora of North America", the field guide to all the plants of the USA and Canada, chose to do. To make it even more complicated, there is evidence to suggest that Coryphantha shouldn't be a genus either and should all be considered species of Mammillaria! Coryphantha and Escobaria differ from Mammillaria largely in flowering on new growth while Mammillaria blooms primarily on previous year's growth. Coryphantha and Escobaria differ from each other only by details of the seeds. Confused yet? Unless you are a botanist it doesn't really matter. The important thing is to learn about these plants and just call them a name you are comfortable with until the botanists sort out the relationship issues. Don't be shocked, however, if one day we are calling all of them Mammillaria once again.
Photos in the Cactus Chronicle -
Coryphantha elephantidens, Escobaria vivipara, Coryphantha minima
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Cotylendon - January 2008
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Crassula - October 2013
Crassula is a large genus of approximately 300 species of succulents with a worldwide distribution. It belongs to the Crassulaceae, a family of leafy succulents that includes Adromischus, Aeonium, Cotyledon, Dudleya, Echevaria, Kalanchoe, Sedum, and several other ornamental genera. The latest number of Crassula species, including nearly all cultivated ones, are from Africa (especially the eastern Cape of South Africa). However, right here in California we have three native species: Crassula aquatica, C. connate, and C. solleri. Unfortunately these species are small and weedy, and therefore not ideal for cultivation. Crassula aquatica has the rare distinction of being an aquatic succulent. It often grows in vernal pools that dry out in summer so its succulent nature allows it to survive later in the summer than other plants in that habitat.
Crassula is distinguished from the most of the rest of the family by having as many stamens as petals, and having opposite leaves. Other African members of the Crassulaceae have twice as many stamens as petals. Depending on the species, Crassula can range from being a tiny herb only an inch or two high (e.g. C. susensis) to a large shrub like the common Jade Plant (C. ovata).
The genus runs the gamut from beginner plants that are virtually indestructible to difficult winter growers that are intolerant of water in the summer, but at the same time prone to drying up is insufficient moisture isn't provided. It is imperative to look up the cultural conditions for your particular your particular plant as there is no singular bit of advice that can cover all Crassula. There are some generalities that cover most cultivated Crassula. They are usually winter growers. They start growth in October, grow until the days get too short, sit out the worst of the winter, and then grow again until the weather warms in early summer. Most are dormant during the summer. This works well in our wet winter/dry summer climate.
Propagation of almost all Crassula species is most easily done by vegetative offsets. Cuttings should be taken when the plants are in active growth, early spring being the best, left to dry for a day or two, and then simply potted in the same mix as the original plant. Rooting is almost always rapid and new growth appears in a week or two. Many species can be started from leaf cuttings so long as you include the base of the leaf where it attaches to the stem. Propagation from seed is possible but can be surprisingly difficult. Seed planted in October or November. Germination is sporadic, and keeping the seedlings alive is often a challenge.
-- Kyle Williams
Special thanks to Tom Glavich
Photos in Cactus Chronicle:
Crassula ausensis sup. titanopsis, Crassula arborescens, Crassula aquatica
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October 2008, November 2007
Crested and Monstrose plants are deformed versions of otherwise normal plants caused by abnormal growth. Specifically, they exhibit deformed growth caused by the growing points (called meristems) of the plants forming new tissue in an improper manner. The exact nature of the deformed growth separates crested plants from mon- strose ones. While most often seen, and coveted in cacti and other succulents, crested and monstrose growth can occur in any kind of plant.
Normal plant growth takes place at a single point at the tip of each branch or stem called the apical meristem. The apical meristem produces new cells that go on to form the rest of the plant, but the meristem itself remains a single cell. This growth from a single point is why stems are generally round and regular in shape. The apical meristem also suppresses the growth of dormant meristems along the stem, especially those closest to the tip.
Crested plants (also known as fasciation) are distinctive in that they grow in a linear or wavy shape. This growth can be so unusual that it can be hard to tell that a crest and normal form of a species are really the same thing! This growth form results from a mutation in the apical meristem where instead of remaining a single cell it starts forming many new apical meristems all in a horizontal row. This means that instead of one apical meristem controlling growth, you have dozens, if not hundreds, all trying to produce new growth at the same time. This growth could be considered regular irregularity in that line of meristems is abnormal, but they grow in an organized fashion giving us the beautiful and strange crests we grow.
Monstrose growth also results from meristems going haywire. In this case the apical meristem can no longer control and suppress the dormant lateral meristems, so they all start growing. That creates a malformed, often overly branched, plant that looks strange to some and fascinating to others.
Several factors are known to cause plants to crest or go monstrose. Sometimes a random mutation causes this. Usually this mutation is not passed on to any seeds it produces. It can also occur from a hormonal imbalance in the plant. External factors include certain fungal or bacterial infestations, or even environmental damage than normal plants of the same species. They tend to be more attractive to spider mites and mealy bugs than normal plants, and a careful eye must be kept on them to keep good growth.
Culture of Crests and Monstrose Plants
Crested and monstrose plants are grown exactly as normal plants of the same species. Some have weak roots, and only grow well as grafts. However, others are robust growers, and do perfectly well on their own. Careful observation of the health of the plant, and comparison to healthy normal growth plants of the same species will quickly show whether grafting is necessary. You can also research your plant online or by asking other growers to find out the special needs of your particular crest or monstrose. These plants tend to be more sensitive to poor growing conditions, getting sunburn quicker, and getting un- sightly brown spots more easily than normal plants of the same species. They tend to be more attractive to spider mites and mealy bugs than normal plants, and a careful eye must be kept on them to keep good growth.
Propagation of crested plants
In most cases, Crests and Monstrose plants flower and produce seed, just as other plants do, but less often. Good strong growth is probably the best way to produce a flowering crest. Crests and Monstrosity are not generally transmitted by seed; however, seed from a genetic mutant plant (i.e. not from pathogens or environmental factors) is much more likely to be a genetic mutant than that from a normal plant. The genetic mutation is more likely to be the same as the parent, but any other mutation is also possible.
The most common method of propagation of crested plants is vegetative. Cuttings of crests are often grafted to speed growth and to preserve special growth forms. Cuttings of varieties that are on their own roots will generally root easily, as long as the cuts are taken during the growing season. After a few days drying, the cut sections are simply stuck into slightly moist potting soil. After a few weeks, there will be sufficient roots to resume normal watering.
—Kyle Williams, with special thanks to Tom Glavich
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Cucurbitaceae - July 2014, April 2010
Cucurbitaceae are a large family of plants consisting of nearly 120 genera and over 800 species. In its non-succulent form this family produces many important food crops including melons, cucumbers, pumpkins, and squash. This plant family has genera that have been grown for over 10,000 years. It should be no surprise then that the succulent form of this family generates a vine that emerges from a caudex root system that ultimately forms uni-sexual flower.
Many of the more collectable cucurbits are tropical caudiciforms, requiring warm weather for growth, and sensitive to cold and wet. Typical growth habits start with a fast growing vine starting in late spring to early summer, ending growth in late September or October. When the vines die back, they can be cut off, and the caudex removed to a garage or basement for winter storage. Most succulent cucurbitaceae are very vigorous growers and will grow much faster and better if given free root run.
One of the rarest of succulents is Dendrosicyos socotrana, a tree cucumber from the Island of Socotra. This island, off the coast of Yemen is known for its endemic species and bizarre plant life. It is an Indian Ocean equivalent to the Galapagos Islands. This monotypic species has a large trunk reaching to 20 feet tall and 3 feet in diameter, and prickly leaves.
Another rare and beautiful cucurbit is Seyrigia humbertii, from a genus found only in Madagascar. In has a small caudex, with blue green felt covered stems growing like very thick grass. Also from Madagascar is Xerosicyos. There are four species associated with this genus, the most common of which is Xerosicyos danguyi. This species has quarter sized glaucus green leaves widely spaced on sprawling stems. It is relatively easy to grow, as long as it is kept dry in winter and not allowed to get much below 40 degrees.
One of the newest Cucurbits to enter cultivation is Odosycios bosseri, a caudiciform species from Madagascar.
Momordica is a medium sized genus from the old world tropics with about 60 species, some of which form caudices. The most popular is Momordica rostrata which forms a pleated cone. Climbing vines start from the tip of caudex, grow through the summer, and die back in the fall. Also from the old world tropics is Kedrostis, a genus of about 35 species, the most common of which is Kedrostis africana, a caudiciform plant that is found in many collections. Similar to Kedrostis is Gerrardanthus, differing only in the fruits and details of the climbing tendrils. Both genera have several members that form very large caudices. They are rampant growers, and do well in the ground during the growing season. Gerrardanthus macrorhizus is found in South African. The caudex from which the vine grows can, in habitat, grow up to 5 feet in diameter which the vine reaches 30 feet in length. This plant requires partial shade and fast draining soil.
The new world equivalent to Kedrostis and Gerrardanthus is Ibervillea, with several species known, and with new species being found in the jungles of Southern Mexico and Central America. Ibervillea sonorae and Ibervillea tenuisecta are both readily available and easily grown. They form light gray elongated caudices. Like the African species, they won’t tolerate cold, damp roots for long.
Other less common members of the family include Anisosperma from Brazil, Cephalopentandra from Tropical Africa, Ceratosanthes from the Caribbean and South America, Coccinia from Africa and Asia, Corallocarpus also from Africa and Asia, Cyclantheropsis from Africa and Madagascar, Eureiandra from Africa and Socotra, Neoalsomitra from India to Australia, Telfairia and Trochomeria from Africa, Zehneria from the Old World Tropics, and Zygosicyos from Madagascar. Continuing exploration of the tropical forests of Africa, Asia and the Americas will bring new genus and species to the collector.
Photos in Cactus Chronicle:
Female Gerrardanthus macrohizus, Ibervillea sonorae
References:
G. Rowley, Name that Succulent
G. Rowley, Caudiciform and Pachycaul Succulents
A. Sajeva and M. Costanzo, Succulents, The Illustrated Dictionary
Tom Glavich March 2002 -- Edited, Steve Frieze September 2009
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Cycad caudiciform - January 2008
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Cyphostemma - September 2016, July 2012 & 2010
Cyphostemma is a member of the Vitaceae or grape family. The members of this genus span the range from extremely easy to grow plants to real challenges. Many of the species will grow large, given time, good root room, lots of fertilizer, and water during the growing season. This genus contains some of the most striking pachycauls and caudexes of the entire plant world.
Most Cyphostemma will set fruit in Southern California. In almost all cases, the fruit is toxic to humans and most pets, although freely eaten by birds. The seeds in the fruit are ripe when the fruit turns color, usually bright red.
The key to success with these plants is to pay attention to the native habitat. Cyphostemma juttae, common in many collections, easily obtained, and often a show winner, comes from South Africa.
Cyphostemma betiforme is still another unusual species originating from Kenya. They form rather large caudexs and stand up to five feet tall. Another highly valued species is Cyphostemma uter. This plant comes from Namibia where it grows in very arid conditions
Propagation is easy from cuttings and seeds. Seed of all the common and even some of the truly rare species is sometimes available through the CSSA or through some of the better South African and US seed dealers. Germination is erratic (days to months), so only one seed should be sown per pot. The seedling mix should be sterile and organic, and hold a lot of water. Scarring the seeds to allow water penetration helps. The seeds should be completely buried to provide uniform moisture. A plastic bag over the mix will help keep soil moisture constant. The bag should be removed as soon as any sign of green appears, the seedling leaves are large, and will rot if they touch the plastic.
Softwood cuttings can be taken when in active growth. Rooting does not require or even seem to benefit from hormones. This is a good way to propagate overgrown specimen plants. Growth of all species is greatly aided by ample root room, but the more sensitive varieties must be lifted in the fall as they go dormant.
Photos in Cactus Chronicle:
Cyphostemma seitziana, Cyphostemma juttae, Cyphostemma betiforme,
Cyphostemma uter
References:
Gordon Rowley, Caudiciform and Pachycaul Succulents
Tom Glavich June 2003 - Edited, Steve Frieze, June 2012
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Beaucarnea - April 2014
Beaucarnea recurvata, the Ponytail Palm, is an incredibly popular plant grown by everyone from succulent enthusiasts to people with a black thumb (the latter usually as a neglected houseplant). While it looks nice as a small to medium sized houseplant, mature plants grown in the ground are really where you can see this species shine. What most people don't realize is there are several other species in the genus. The species are fairly similar (to those of us that don't focus on the genus), mainly varying in overall size, degree of branching, size of caudex, etc. Most species are sizable landscape plants, though B. compacta stays small enough to be part of a modest sized landscape where space is an issue.
. . . the characteristics of being woody and having grass-like to sword-like leaves. Cultivation of most species is easy. Nearly all can grow in the ground, and most, but the largest species, can live happily in pots. They are mainly warm season growers so provide some water during the spring through fall to get them to look their best.
-- Kyle Williams
Photo in Cactus Chronicle:
B. recurvata outside
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Blossfeldia & Frailea - January 2018, January 2016, November 2012, Frailea June 2011
This month we are going small, very small, for our cacti. We are focusing on two genera, one of which is literally the smallest cactus species of all and the other likely has the smallest average plant size for a cactus genus with numerous species. This should be a heads up for those of you that think you are out of space for more plants. Not with these guys! Most of the species we are looking at this month could live permanently in a 3” pot or less.
Frailea is a genus of approximately 20 species from South America, with most species in Brazil. In general they are quite small, with individual heads roughly the same diameter as a quarter. They clump, have small to no spines, and usually have a depressed or sunken center. In times of drought the plants will contract and sink below the soil level. This can help the plant retain water by getting it out of the hot sun.
Individual plants often make two different types of flowers. The prettiest ones are big and open, generally bright yellow. These flowers are how the plant cross pollinates with other plants (i.e. the normal way flowers work). That allows for genes of different plants to combine allowing for more diversity within the species. The other, more unusual, flowers are referred to as cleistogamous, or hidden flowers. They don’t seem hidden at first. In fact you’ll see a big flower bud developing like normal, but it never opens. Eventually it falls off and the fruit develops and produces seeds. What happened was the flower intentionally remained closed and self-pollinated. This ensures seed production and therefore a higher chance of producing baby plants than with an open flower that may or may not get pollinated. The down side is the plants are very inbred, so any bad traits of the parent could be as bad or worse in the progeny. Of course, good traits can get passed along too!
Blossfeldia is genus containing the single species Blossfeldia liliputiana from northern Argentina and southern Bolivia. It clumps readily with individual heads being smaller than a dime! This makes it the smallest cactus in the world. The flowers are similarly tiny. Blossfeldia is rarely seen in cultivation because it is hard to get the dust-like seeds to germinate and when they do, the plants are nearly microscopic. When they are seen for sale it is usually in grafted form. It is easy to grow that way though it will grow bigger this way than on its own roots. Previously, botanists thought Blossfeldia was related to Parodia or Frailea but modern DNA research has found it to be a very distinct lineage of cacti all its own.
Photos in the Cactus Chronicle -
Frailea asterioides, Frailea magnifica, Blossfeldia lilputana
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Bombax - June 2009, September 2008 & 2007
Bombax ellipticum is the only member of this genus commonly seen. The Bombaceae is a relatively small family, which holds the genus Bombax along with Ceibia, a tropical genus with some pachycaul trees, and Adansonia, the largest of all of the pachycauls. There are a few other species in cultivation, but since they are tropical and large, they are not often seen in California.
Bombax elipticum develops a large semi-spherical caudex, quickly. It is a favorite of many growers. Each caudex is different in shape and color. They are easily grown, requiring only lots of fertilizer and water during their growing season. They are deciduous, losing all or most of their leaves in the fall, and leafing out again fairly late in the spring.
Some of the best caudexes (sic) are produced by abusing the growing plant and turning the pot on its side for all or part of a growing season. This produces the most interesting shapes, and the best looking plants. Many growers will cut off the trunk periodically to force new branched growth and more growing tips. All of these help produce the caudexes with great character that frequently grace our shows.
Photo in Cactus Chronicle:
Bombax elipticum
References
M. & G. Irish, Agaves, Yuccas and Related Plants
U. Eggli ed. Monocotyledons. Dicoledons
Tom Glavich July 2005
Edited by Steven Frieze, 2009
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Borzicactus - February 2013
for detailed information, see full article
Borzicactus and Cleistocactus by Leo A. Martin,
Central Arizona Cactus and Succulent Society (CACSS) website http://centralarizonacactus.org/assets/article/genera/CACSS_Article_Borzicactus_Cleistocactus_Leo_Martin.PDF
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Brachystelma - August 2014
Brachystelma is a big genus of 100 species or more. It has the largest range of these genera as it occurs from South Africa through India and Southeast Asia, and even to Australia! The largest number of species grow in South Africa. The species most commonly grown have a similar habit to Fockea and Raphionacme, but are noteworthy in having spectacular flowers that are similar to Stapeliads (the other genera have small nondescript flowers). The most commonly grown species, B. barbarae doesn't look like a succulent at all from above as it has large green leaves. Only when you see the tuber do you realize it is a desert plant.
Cultivation for the most commonly grown, South African, species of these genera is fairly easy. Treat as a summer growing succulent that doesn't like to dry out completely. Most plants will go dormant or semi-dormant in the winter and shouldn't be watered as often, though they seem fairly tolerant of our wet winters if the soil is well drained. The tubers/caudex grow the fastest when buried, so it is advantageous to grow them that way for several years before raising them.
Photo in Cactus Chronicle:
Brachystelma vahmeijeri
-- Kyle Williams
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Brazilian cactus - August 2011
A Melocactus was very likely the first cactus seen by a European explorer, and certainly one of the first to be brought back and successfully grown. They were known in English collections by the late 16th century, less than 60 years after Columbus’ first voyage.
Melocactus are one of the many genera of cacti found in Brazil an enormous country with many ecosystems and climates. Many of the genera are typically associated with this country (including Melocactus mentioned above) such as Buiningia, Discocatus, Frailia, Rhipsalis, Ubelmannia, and Zygocactus. Other genera are less often associated with the Brazilian ecology but thrive in habitats throughout this country include Echinopsis, Monvillea, Opuntia, Parodia, and Wigginsia. In fact Brazil is how to over 60 genera of cacti that cover almost the entire geographic area of this country. Not mentioned yet but noteworthy are the plethora of Epiphyllum species found in the tropical areas of Brazil and the Brazilicereus native to this country only.
Melocactus are immediately recognizable by the large cephalium that develops on mature plants. Melocactus grow as normal appearing, but flowerless, globular cacti until they reach maturity. This can take from 6 to 15 years in cultivation, with a greater range in habitat. Once they reach maturity, the body stops growing vigorously (it still grows slowly). Most of the plant energy goes into producing a cylindrical flowering and fruiting structure known as a cephalium. This is usually white, with short hairs of yellow, orange or red. As the years go by, the cephalium becomes more cylindrical, with the base becoming more colorful The flowers are usually a redpurple, and the fruits are almost always a bright red, to attract birds. With age, the cephalium can grow to 18 inches or more in height, occasionally bifurcating or trifurcating.
Melocactus are native to a large region, Brazil to Southern Mexico, including a good part of the Caribbean. As might be expected, cacti from the tropical regions, particularly coastal regions are sensitive to cold and wet. Cold and wet conditions can cause scaring of the body, which usually appears as brown or tan lesions on the skin. A few of these are unavoidable, but a badly scarred plant quickly becomes unsightly. At the same time, almost all of the Melocactus expect high humidity and a higher moisture level than might be expected. Many grow within sight of the ocean, or in some of the more tropical and humid regions of Brazil. They like water, but demand good drainage.
Melocactus are generally solitary, so the only means of propagation is through seeds. Fortunately they produce plenty of seed, and these germinate readily, particularly when the weather is warm. Keep the seedlings protected from direct sun, and moist until fairly large. Although it is several years from seed to a flowering plant, most of the Melocactus have magnificent spination and vividly colored bodies, which make keeping them a pleasant task.
Frailea are "smallish" many stemmed cacti that many experts now view as short lived. Some now speculate that Frailea may function as a annual in habitat sowing seeds from the base of a mother plant. In habitat, Frailea are found in ecological niches where there are large rock formations and just a couple of inches of soil.
Endemic to Southern Brazil, Discocactus are prized by the collector if for no other reason that the elegant wooly cephallun the plants develop in maturity. Similar to the Melocactus, flowers originate from the ceplhallun which can reach two or more inches in heigth.
Photos in Cactus Chronicle:
Frailea species, Discocactus psuedoinsignis in a sandy habitat,
Melocactus azureus entered by Rosemarie Sauer 2003 CSSA Show,
Brazilicerus phaeacanthus
Reference:
The New Cactus Lexicon, David Hunt
The Brazilian Cactus Project (web), Marlon Machado
Tom Glavich April 2004, Photo by T. Nomer
Steve Frieze, August 20011
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Bromeliad - April 2017
Bromeliads is the term used for members of the Bromeliaceae, a family of plants known for their epiphytic habit (i.e. growing on trees). This is a very large family of over 51 genera and 3,500 species. For comparison, the cactus family (Cactaceae) has more genera but only half the number of species as Bromeliads. Obviously, twice as many species as all cacti combined are too many species for a plant of the month! Fortunately, there is an easy way to limit our scope in a way that makes sense for a cactus and succulent club, focus on the species that are terrestrial and adapted to the xeric conditions we normally associate with cacti and succulents.
Most Bromeliads are tropical rainforest epiphytes with a rosette shape that allows the plant to form a vase or bowl like shape which catches water. Why do rainforest plants need to catch water? Epiphytes live on the branches of trees, which means there is no moist soil for the roots to tap into. Orchids and jungle cacti deal with this through succulence, but Bromeliads deal with it by catching water in cup shaped leaves and absorbing the water directly through those leaves (instead of the roots) using modified hairs called “trichomes”. That is an ability very few other plants possess. For those of you who’ve never had the opportunity to go to the Central or South American tropics, you can see Bromeliads, Orchids, and jungle Cacti all on the same tree branch! No open space in the tropics goes unused, even a branch.
Bromeliads and Cacti share a very interesting feature of their distribution. They are both found native only North and South America, and nowhere else in the world. They are the two largest plant families to be found exclusively in the Americas. This strongly suggests that both families evolved at a point after the Americas separated from the other continents.
Our interest this month is on the Bromeliads that are terrestrial (i.e. grow on the ground) and are xeric, or adapted to dry, desert like conditions. Unlike most Bromeliads whose roots are used only to attach the plant to a tree, these species take up water through their roots like normal plants. Though it is quite possible that they take in some water through their leaves when opportunities arise. Because of their “normal”, non-epiphytic, habit it was assumed terrestrial species were the most primitive member of the family. Modern DNA research has found this not true at all. In fact, the earliest branch of the family (that still exists) is a carnivorous bromeliad that catches insects in its water filled pitchers!
The most commonly grown genera of terrestrial Bromeliads are Deuterocohnia Dyckia, Hechtia, and Puya. Dyckia and Hechtia are small enough to make nice potted specimens. They look a lot alike, despite being distantly related, but have very different flowers. They both have colorful, serrated leaves often covered in fuzz or felt. Deuterocohnia is popular for forming big mounds made up of small rosettes. Puya are generally very large plants that are much too big for a pot, or even smaller landscapes. If you have the space for a Puya you will be rewarded with some of the most unusually colored flowers in the plant kingdom, such as metallic blues, greens, and purples.
-- Kyle Williams
Photos in Cactus Chronicle:
Puya berteroniana flowers, Deuterocohnia brevifolia, Dyckia Hybrid
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Buiningia - May 2014
Coleocephalocereus is a genus of approximately six species of with a columnar habit. Many know the genus as Buiningia, but botanists have determined Coleocephalocereus is the more proper name. What makes this a standout genus worthy of cultivation (and easy to identify) is the lateral cephalium running down the sides of mature plants. "Lateral cephalium" probably made several people's eyes glaze over, but don't worry, once you see one you won't forget it! Coleocephalocereus is a mouthful to say but in English it means "the Cereus with a sheath head" which makes a lot of sense.
Most people are familiar with Melocactus because it grows like a normal green cactus for several years but then starts to produce a strange fuzzy and spiny "head" (that's what cephalium means) which makes flowers. Over the years the this fuzzy head grows taller and taller while the normal green part of the plant remains the same. Turns out that Coleocephalocereus does the same thing but in a "smarter" way from a growth standpoint. While Melocactus completely stops producing a normal green stem for the rest of its life, Coleocephalocereus produces the cephalium on one side of the plant only, meaning the stem can keep growing up. This gives a very unusual but beautiful look, almost like a beard on the plant.
They are from tropical regions and appreciate warmer temperatures. It is best to keep them at a minimum of 50 degrees in the winter, but they can be grown cooler (but never below freezing) if kept dry in the winter. Cool and wet makes them prone to rot. During the summer they appreciate more water than the average cactus.
-- Kyle Williams
Photos in Cactus Chronicle:
Coleocephalocereus aureus, Coleocephalocereus brevicylindricus
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Bulb - January 2016
caudiciform - October 2006
Bulbs are an extreme form of geophytic succulent. They produce leaves, sometimes not, when there is available moisture, and they dry back to the surface or below when the moisture is gone.
Bulbs are native to both hemispheres, and all the continents except Antarctica. Australia, a continent with few succulents in the conventional sense has a wealth of bulbs. The Mediterranean region and the inner parts of Asia, have an extraordinary range of bulbs. There are an incredible number of families and species to choose from. Attention needs to be paid to the growing conditions the bulbs come from (mostly winter or summer growing, and the tolerance to water out of season.) Some bulbs grow in spring and summer, flowering in late fall, some in the fall, flowering at any season, sometimes even when there are no leaves.
The principal families of bulbs grown by succulent collectors are the Amaryllid Family, represented here by the New World species Habranthus acutifolia, and the South African Haemanthus deformis, most barely known in cultivation.
Amaryllids tend to be large. The other extreme is represented by the Hyacinth family, with many wonderful small bulbs. Just one is represented here, Ornithogalum juncifolium, with bulbs only 1⁄2 inch in diameter, exposed, as they would be in habitat.
-- Tom Glavich, October 2005
Photos in Cactus Chronicle:
Ornithogalum juncifolium, Habranthus acutifolia, Haemanthus deformis
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Bursera - September 2018, August 2013, March 2008 & 2007
Both Bursera and Commiphora are members of the Burseraceae. Bursera are confined to the New World, mostly from Southern California through Guatemala.
They all do best when watered in the summer in Southern California. They will all tolerate being left unprotected, outdoors during the winter rains, Any standard succulent mix will do as a potting medium. Growth is much more rapid when they are fed. If grown in an open mix they can take an amazing amount of water in the summer, and will reward the grower with substantial growth and trunk thickening. All of the plants do well when treated as bonsai, and pruned to expose the geometry and structure of the trunk and bark. Planting in the ground will greatly accelerate the growth rate.
Bursera is a wide spread genus, with a range that extends from California into South America. Many of the species are beautiful trees with red or brown peeling bark, rarely seen in cultivation. Some of the tree-like species are very vigorous growers, going from a foot to 6 feet or more in a just two years, in a medium size pot. Most Bursera are aromatic, with wonderful woodsy fragrance from their leaves and bark. Most of the species are worth growing and can be made into show specimens by suitable pruning. Many of the larger species require hard pruning every year to avoid having them turn into trees. Species frequently seen are Bursera fagaroides, Bursera microphylla, with very small leaves, Bursera multijuglans (with red peeling bark), and Bursera simplex. There are many other species from Central and Southern Mexico, and Central America that should be grown and shown.
Vigorous growth is also found in well fed and watered plants.
-- Kyle Williams, Special Thanks to Tom Glavich
Photos in Cactus Chronicle:
Bursera fagaroides, Bursera fagaroides leaf
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Acharagma - February 2017
Acharagma is a tiny genus of just two species of small cacti from northern Mexico. We are including them along with Escobaria this month because they started out being described as members of that genus. Over time they were separated out in large part due to groves on the tubercules that the rest of Escobaria lack. This separation has since been vindicated by DNA study. It turns out Acharagma is not closely related to Escobaria at all, and is instead a close relative of Lophophora (Peyote) and Obregonia!
While all plants in this group are relatively small, many can form good sized clumps in time (much like Mammillaria). Some of the variation between species include having globular plants and more cylindrical, upright plants. Flowers vary from yellow to pink. Some species are covered in dense white spines while others are more sparsely covered, allowing the green body of the plant to shine through. A large number of species produce tap roots. Cultivation is similar to Mammillaria and other small cacti. While some members of these genera are renowned for their cold tolerance, keep in mind many species come from warm climates. Of course that isn't much
of an issue for us in California, but anyone growing them in cold climates needs to make sure they pick the cold tolerant species. Most species take general cactus care and do well in smaller pots, and so make nice additions to any collection.
-- Kyle Williams
Photo in Cactus Chronicle:
Acharagma roseana
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Adenia - August 2018, July 2011, May 2009 & 2007
Adenia is entirely unrelated to Adenium, and is a member of the Passiflora or Passion Flower family. Most of the collectable Adenias have large bases that support climbing stems or branches. In habitat they are often found in brush, with the branches scrambling up through brush, or alternately growing in a open area, entirely covered by a sprawling mass of live and dead stems.
In cultivation the sprawling stems are regularly pruned to keep the plant good looking in a pot (as well as transportable). All of the Adenia are cold sensitive, particularly when young, and should never be exposed to cold and damp. Collectable species include Adenia globosa, with a green spherical body, resembling in texture and color a giant avocado.
Another wonderful spiny species is Adenia spinosa. In this species the body is gray brown at the base, fading to an olive green on the upper surface. A forest of dense spiny branches comes from the caudex. Adenia glauca has a base much like an Adenium, before tapering to a vine like stem.
-- Tom Glavich June 2004
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Adenium - August 2016, June 2012, August 2009, May 2007
Adenium is a member of the Apocynaceae, and a relative of Pachypodium, Oleander, and Vinca. The Apocynaceae is home to many showy flowering plants used for ornamental and medicinal purposes. Oleander is a staple of much of Southern California Gardening; Vinca is grown around the world.
Adeniums are native to Africa and very large clumps of Adenium obesum can be found in selected areas of Tanzania. The plants found in sub-Saharan Africa typically have think stems and an enlarged base and root system known as the caudex. Propagation occurs most successfully from tip cuttings (about 5 inches from the growing point of a branch) although many wholesalers now generate new crops from seeds.
Adeniums are relatively easy to grow if you follow a couple of important rules. Adenimums should receive absolutely no moisture from November through March when they go dormant Resume watering when you observe leaves emerging from existing branches. They should also be kept warm during this period of time either by placing them in a green house or next to a house wall that receives heat from a climate control system. Some growers place their plants in their garages in late fall to force dormancy, and protect them from cold and damp. During the growing season, Adeniums require good fertilizer, and lots of water. Adenium are being hybridized for the caudex shape and for flower color. Hobbyists seek out and treasure large caudexs on the Adenimums that they exhibit.
Adenium somalense is another outstanding caudiciform plant found in an area from Somlia down through Kenya and Tanzania. The leaves of this plant are greenish with a white vein down the middle of the leaf. The flowers are smaller than those for Adenium obesum and are pinkish to white at the base of the blossom.
Adenium arabicum is another species that produces a large caudex and a plethora of lovely pink blossoms that rival any of the other plants found in this genus. You can distinguish Adenium obesum from arabicum by the texture of the bottom of arabicum leaves (it has a feathery feel to it).
Photos in Cactus Chronicle:
Adenium arabicum, Adenium somalense, Adenium obesum (Tanzanian habitat photo - S. Frieze)
References:
G. Rowley, Caudiciform and Pachycaul Succulents
M. Dimmit, G. Josephs, D. Palzkill, Adenium: Sculptural Elegance, Floral Extravagance
Tom Glavich April 2003 -- Edited by Steve Frieze, June 2012
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Adromischus - February 2010
Adromischus is closely related to the genera Cotyledon and Tylecodon. There are 29 recognized species of Adromischus all found in southern Africa. When grown in cultivation they require at least partial shade, especially in hotter climates. This plant forms clumping succulent rosettes and expands horizontally. Propagation occurs from stem or leaf cutting as well as from seed. Distinctive markings and colored leaves are characteristic of this genus.
Steve Frieze, February 2010
Photo in Cactus Chronicle:
Adromischus trigynus
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Aeonium - February 2016, March 2010
Aeonium belongs to the family Crassulaceae, one of the largest succulent plant families. All the species (with one exception) have the traditional rosette shape seen in most of the family. It is closely related to Crassula, Kalanchoe, Cotyledon, Tylecodon, Sedum, Echeveria, and Dudleya. The main distinguishing feature of Aeonium compared to other rosette forming genera is that most Aeonium have woody stems. There are Crassulaceae with woody stems that aren’t Aeonium, and Aeonium without woody stems, but generally the character works. Most Aeonium species are monocarpic, meaning that when a rosette flowers it dies, much like Agave and most Bromeliads. In a multibranched species like A. arboreum that’s no big deal since only a small number of branches flower in a given year. It is a big deal in the unbranched species like A. nobile or A. tabuliforme as flowering means the entire plant will soon die. However, thousands of dust-like seeds are usually produced, so you can grow your own replacements.
The vast majority of Aeonium species come from the Canary Islands, a group of islands off the coast of Morocco that belong to Spain. These islands have a Mediterranean climate very similar to that of coastal Southern California. This means the plants are adapted to a climate with cool wet winters and warm dry summers. This makes Aeonium one of the best choices for a succulent landscape as the plants can survive and even thrive purely on natural rainfall alone. Of course some supplementary water in the summer is appreciated by the plants. Frost is extremely rare in the Canary Islands (except on the mountains) so they may take damage if we get a frost in our area, but if the frost is light they should recover.
The most commonly cultivated species is A. arboreum, a shrubby species with long stems. The wild form of the species is green, but most people know it from the purple to black cultivars such as ‘Zwartkopf’ or ‘Cyclops’. Aeonium canariense is also extremely common. If you see a clumping plant with large rosettes that stays low to the ground then it is very likely this species. The other species very commonly encountered is A. haworthii a very densely shrubby species with small rosettes and very thin stems.
The species above are the big three that everyone thinks of when Aeonium is mentioned. Aeonium nobile is a single rosette, stem-less species with rosettes 2-3’ across and leaves as thick or thicker than an Echeveria! Aeonium urbicum has gray-green leaves and can reach 6’ high or more on an unbranched stem. Aeonium sedifolium is the smallest species with fat, oval shaped leaves with red stripes. Aeonium smithii is an oddball in having leaves and stems covered in wavy hairs. No discussion of Aeonium is complete without mentioning the show stopping A. tabuliforme. This is a stemless, unbranched species with an almost perfectly flat rosette with hundreds of leaves that can reach 2’ in diameter. It has a reputation for being hard to grow, but the only difficulty is that it is somewhat picky about having a summer dormancy period and is prone to rot if you insist on watering it in hot weather.
Greenovia is a small genus of just 2-4 species, also from the Canary Islands. It is very similar to Aeonium and has been considered part of the genus by some, though most botanists consider them distinct. The species look like a stemless Aeonium with blue green leaves. The most unusual feature of the genus, one that makes them instantly recognizable during the summer, is that leaves fold together into an egg or tulip shape when dormant. Care is similar to Aeonium, but make sure to keep them dry during the summer as they can rot if in their dormant period.
-Kyle Williams
Photos in Cactus Chronicle:
Aeonium sedifolium, Aeonium tabuliforme, Greenovia aurea
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Agave - November 2017, March 2014, May 2010, June 2009 & 2007
Agaves are one of, if not THE, most popularly grown succulents in California and the Southwest. It is hard to go down any street in our region without seeing at least one Agave americana, A. attenuata, A. potatorum, or a host of other species. They are easy to grow, come in a great variety of sizes and shapes, and most thrive on neglect. No wonder they are so popular!
Agaves, like the Cacti, are entirely new world in origin, although many members have been naturalized around the world. Agaves are native to Southern North America, Mexico, Central America, Northern South America and the Caribbean. A few species are native to the deserts of Southern California. There are roughly 200 species of Agave and countless varieties and cultivars, with new species being discovered regularly. Some species are so common in cultivation that you practically can't give them away while others (such as A. albopilosa) command $100 or more for a small plant.
Many people shy away from Agaves because they think the plants are all spiny giants that take over half of your yard. While species like A. americana and A. mapisaga certainly fit that description, there are lots of well behaved small to mid-sized species such as A. victoriae-reginae, A. potatorum, A. isthmenensis which can even be grown in a pot (hopefully so or we won't have any entries for our contest!). If stiff leaves and sharp spines are the problem then A. attenuata is perfect for you. Its leaves are so soft and lush that it would look right at home in a tropical planting instead of a xeric one.
Agaves are easily grown from seed. Although many of members of this genus grow very large with age, they are particularly good looking as seedlings, and can be kept small for many years in pots. They thrive with regular feeding with any general purpose fertilizer. Their appearance is best when they are cleaned regularly, with debris removed from the leaves, and dead leaves removed to prevent insects from making homes. Many offset freely, and these offsets can be removed and repotted, giving a steady supply of small plants. Many growers keep the offsets, and dispose of the mother plant, keeping size, health and condition under control. Agave flowers are spectacular with spikes that sometimes reach as high as 20 feet. After flowering, the agave mother plant dies back.
-- Kyle Williams
Photos in Cactus Chronicle --
Agave funkiana, The rare and expensive Agave albopilosa, Agave applanata 'Cream Spike'
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Aloe - February 2017 & 2014, April 2013, January 2011, January-February 2009, February 2008 & 2007
clusters - February 2017
Aloe is one of the most popular genera of succulents, especially in Southern California. In fact, Aloe vera may be the most widely cultivated succulent in the world, owing to its medicinal properties. Most species small herbs to shrubs, though some species (most notably A. dichotoma and A. barberae) can reach tree size. With over 500 species, and at least as many hybrids and cultivars, there is an Aloe for almost any situation and taste. Aloe species are native to most of the drier parts of Africa, including Madagascar, with a number reaching the Arabian Peninsula.
They are naturalized in every Mediterranean environment in the world, as well as some temperate and tropical regions. All but a few Aloes will grow readily in Southern California, either in the ground, or in pots. When in the ground they require minimal care, existing happily on only natural rainfall in most years. Summer growing species will appreciate some summer water. The sheer number of species and habitats make blanket statements on culture impossible, but most will thrive under the general care you give other succulents, so long as you know if you have a summer or winter grower.
Aloes combine interesting form and foliage with beautiful flowers. Most species have orange, yellow, or red flowers that are attractive to Sunbirds in their native Africa. In the Americas Hummingbirds regularly visit them. These birds are great at pollinating flowers and it isn't unusual to see fruit develop. Those looking for other colors can find species with white or even green flowers. Some species, such as A. tomentosa, even have hairy flowers!
Aloes are relatively pest free, though they are as susceptible to a mealybug outbreak as other succulents. Two serious pests of Aloe are rust and mites. Aloe rust, which produces red ringed spots black or brown spots on the leaves is a fungal disease, and can be controlled with any fungicide. Aloe galls are produced by the Aloe mite. These nearly invisible insects cause deformed flower stalks or leaves. The plant should be removed from all others, and is best destroyed, although eventual cure is possible with miticides.
This month our particular focus is on Aloe clusters in smaller pots (maximum pot size 6”). A cluster would simply be any Aloe plant with three or more heads on it. Obviously the pot size limitation means that smaller species would be best. One of the best choices for this category would be the colorful hybrid Aloe cultivars that have become popular in recent years. But of course any Aloe with multiple heads that can fit in a smaller pot are welcome.
-- Kyle Williams
Photos in Cactus Chronicle:
Aloe x ‘Christmas Carol’, Aloe dorotheae, Aloe descoingsii
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Anacampseros - January 2015, February 2010
Anacampseros is a genus that formerly housed a much larger number of species including the genus Avonia. Anacampseros are found in South African. They form clumping rosettes of succulent leaves. A small caudex forms as the plant ages. Flowers bloom periodically during the summer on sunny days only.
Steve Frieze, February 2010
Anacampseros has around 30 species, primarily from South Africa and adjacent countries, with one species native to Australia. For the most part the species tend to have fleshy rhomboid, or diamond shaped, leaves, very soft and fleshy stems, and have white hairs at the base of the leaves. Some species are covered in a netting of thin white hairs that resemble a spider web! The most commonly grown species is probably A. rufescens, particularly the bright pink variegated form known as 'Sunrise'. Anacampseros stays quite small and most tend to form clumps over time. One of the nicest aspects of this genus are its flowers. In most species they are large (for the size of the plant) bright pink and produced on long stalks.
-- Kyle Williams, Special Thanks to Tom Glavich
January 2015
Photo in Cactus Chronicle: Anacampseros filimentosa
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Ariocarpus - November 2017, October 2014 & 2011, May 2009
Ariocarpus is one of the most prized and distinctive of all cacti genera. Ranging from Central and Northern Mexico to southern Texas, the genus has some of the most spectacular species of the entire family. Some succulent growers, who otherwise avoid cacti, make this genus their sole exception. There are collectors who collect nothing but Ariocarpus, and have hundreds of plants in their collections. Rare specimens can change hands for hundreds of dollars. Rare cultivars with unusual tubercles can be sold for even more, particularly in Japan. There is no denying that this single genus has generated a world wide cult of devotees.
What about Ariocarpus has led to such popularity? There are several possible reasons. The form of the plant is nearly unique among cacti. Specifically, the tubercules are flattened and triangular, looking very much like succulent leaves. There is essentially no stem separate from the tubercules. Most of the species are quite distinct from each other, and all of them stay small enough to grow in pots. Additionally, they are very slow growing and, until the last 10-15 years, most were rarely seen for sale. Fortunately, a number of growers have been producing Ariocarpus in large numbers and supply is keeping up with demand. This allows people to collect them at a fair price and helps reduce the demand for wild dug plants. Today, the high priced Ariocarpus are usually unusual hybrids or variegates.
Ariocarpus has an undeserved reputation as being difficult to grow. Nothing could be further from the truth. They are no more difficult to grow than many other central Mexican genera, and is well within the cultivation ability of even beginning growers. They come from a hot desert region that gets most of its rain in the summer, with the winter being quite dry. That is the exact opposite of our rainfall pattern, which has led some people to have trouble with them. Wet cool winters will make them rot prone, but it is the water that is the problem not the temperature. So during the rainy season just put them under a bench or somewhere dry that still gets bright light and don't water until spring. This "cool and wet is bad" advice goes for a lot of succulents, but most of the time the plants actually want warmer weather and people bring them inside for that reason (e.g. Euphorbia and Adenium). Don't do that with Ariocarpus. They come from a winter region with colder winters than ours, so they like the chilly weather. It truly is just the water that is the problem.
With all of the fuss we make over this genus, it is important to remember that the plants have had important ethno-botanical uses. The tubercles contain a sticky mucilage, which was often used as glue to mend broken pots. A. kotschoubeyanus was boiled and used as a cure for rheumatism, and several species were used as ‘false peyote’ in religious ceremonies. Cultivation is not difficult, when the home environment of these plants is considered. They grow in mineral soils, with very little organic matter. They all have large tuberous roots. If they are protected from excess organic matter, particularly peat, and watered heavily only in hot weather, (but lightly throughout the summer growing season) good growth will result. There are six species (or more depending on if you want to divide A. retusus), several varieties, and a near infinite set of cultivars.
-- Kyle Williams
Photos in Cactus Chronicle --
Ariocarpus retusus, Ariocarpus Hybrid, Ariocarpus kotschubianus
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Asclepiad - October 2016
caudiciform - March 2011
The Asclepiadaceae or Milkweed family is a large family of succulent and non-succulent plants. This family has a wealth of forms rivaling that found in the Cactaceae, Crassulaceae and Euphorbiaceae families. This month we will focus on the caudiciform or tuberous rooted types, often a very popular plant choice in the exhibitions or shows. The genera Fockea, Brachystelma, Matalaea, Raphionacme, and some of the Cerepegia are all essentially vines. The caudex is typically submerged when found in habitat.
Fockea edulis is one of the most popular specimens. Easily grown from seed, this genus can form an impressive caudex in just a few years if it is left below soil level in ether a pot or other growing condition. Fockeas are relatively easy to grow, can thrive in unprotected conditions even when temperatures drop to near-freezing levels.
Another species that found in nurseries is Fockea crispa (revised to fockea capensis) that possesses a corrugated caudex and crinkly leaves. Fockea multiflora is still another popular species that has an upright conical caudex. Another less well-known Fockea, originating from South African is Fockea comaru. This plant is found in well-drained soil and partial sun. It produces a vine that grows to six feet in length.
The Fockea genus includes the following species not mentioned above: angustiflolia, sinuata, and tugelensis.
Raphionacme is a genus that is a bit more temperamental and is subject to rot. The most common species associated with this genus is Raphionacme flannagani. Raphionacme procumbens, a species originating from South Africa requires well-drained soil and requires lots of sun to thrive. This species was first described in 1895 by Friedrich Richard Rudolf Schlechter.
Other species belonging to the genus Raphionacme include burkei, daronnii, elata, hirsuta, and vignei.
Ceropegia is a genus that originates from the Canary Islands and South Africa stretching to East India. The most common species of Ceropegia is woodii often sold as a house plant. It has heart shaped leaves and small tubers that form at the nodes of the vines. Ceropegia flowers have a tubular structure and assume a variety of colors including black, dark purple, green, and maroon. The many species belonging to the genus Ceropegia include occulta, odarata, campanulata, elegans, and occidentalis.
The last genus of the asclepiad type to be discussed in this article is Brachystelma. This plant usually has a round potato-like caudex. They are the most difficult of all the asclepiads to grow because of their fragile nature. The tendency to encounter rot is much more likely with this genus than with other asclepiads. The flowers are notoriously offensive in smell but extremely beautiful to observe. The advance or patient hobbyist will be richly rewarded by including this genus in their collection.
Brachystelma barberae is a dwarf herb whose leaves emerge from a submerged caudex. In its juvenile state the caudex is circular and as the plant matures the tuber becomes irregular in shape. All plant material on the surface of the plants are covered with coarse hairs and when damaged emit a watery sap.
Brachystelma foetidum is another species of this genus. Named for the offensive scent of the flower (foetidum means a manure-like in smell), this plant originates from Botswana, South African and Zimbabwe. The flower's appearance is dark brown or blackish. Other species belonging to the genus Brachystelma include blepharanthera, circinnatum, constrictum, dyeri, montanum, togoense, and vahrmeijeri.
Photos in Cactus Chronicle:
Brachystelma foetidum, Brachystelma barberae, Fockea crispa, Fockea comaru,
Fockea edulis, Ceropegia woodii, Raphionacme flanaganii, Raphionacme procumbens
References:
G. Rowley, Caudiciform and Pachycaul Succulents
Sajeva and M. Costnzo, Succulents, The Illustrated Dictionary
Tom Glavitch, 2003 - Edited by Steve Frieze, 2011
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Astrophytum - August 2016, September 2013, April 2010
Astrophytum are often one of the first cacti a collector starts with. They are available for pennies (or now quarters) in discount stores, groceries, and home centers. How can anyone resist the $1.29 special speckled Bishop’s Cap? More than a few show plants started out this way. At the same time, growing a perfect, 10 or 20 year old specimen plant is a challenge few growers can master. Fortunately, the genus offers rewards and surprises at every level between, making it one of the most popular of cacti at all levels.
Astrophytum are native to Southern Texas and Northern Central Mexico. They grow in a very arid region, with a porous mineral soil. One of the cultivation difficulties with Astrophytum is their tendency to split open from sudden increases in soil moisture level. To avoid this, keep them in a soil that is very quick to drain, and which has little organic matter. A mixture of pumice and gravel or very coarse sand, with only a little potting soil is best for these plants.
Astrophytum asterias is the smallest of the species. It is the hardest to grow well, prone to splitting if over watered. Astrophytum capricorne is generally the longest spined species. Astrophytum myriostigma is the well known ‘Bishops Cap.’
Astrophytum ornatum from Hidalgo can grow to 12 inches in diameter and three feet in height.
Photos in Cactus Chronicle:
Astrophytum capricorne exhibited by Laura Oster in the 2001 Inter-city Show,
Astrophytum asterias exhibited by Carol and Paul Maker in the 2001 Inter-city Show
References:
Anderson, E. The Cactus Family
Cullman, Gotz and Groner, The Encyclopedia of Cacti
Tom Glavich 2005 - Photos T. Nomer
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Avonia - January 2015, February 2010
Avonia is a small group of roughly a dozen species that generally have very small, often scale-like leaves that envelop narrow stems. The most popular species is A. alstonii due to the beautiful caudex it forms. While the plant is quite small (big ones have a caudex a few inches across), the stout nature of the caudex and the numerous little green stems on top of it make the plant a must have for many succulent collectors. It produces attractive pink or white flowers, depending on the subspecies. While that is the best known species, it differs quite a bit from the other species seen in cultivation. The others, such as A. buderiana are tiny clumping oddities that have paper-like leaves. These papery leaves are so numerous it can sometimes make it hard to even tell if your plant is alive or dead! The flowers are much smaller in these species and no caudex is formed.
-- Kyle Williams, Special Thanks to Tom Glavich
Photo in Cactus Chronicle: Avonia alstonii ssp. quinaria
The genus Avonia originates in South African in Great Namaqualand and Bushmanland. Avonia form a woody caudex, approximately one inch high, which expands as the plant matures. Leaves emerge from the top of the caudex. This plant typically requires partial shade in cultivation and can be sensitive to frost or colder conditions. Although listed as a deciduous plant, many specimen retain their leaves all year long. Flowers are carmine red, white, or pink. Avonia flowers are self-fertilizing and can generate seed if you have only one plant.
Steve Frieze, February 2010
Photo in Cactus Chronicle: Avonia quinaria ssp. alstonii
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Aztekium - May 2015
Aztekium contains three species of small, slow growing cacti that grow in highly inaccessible areas (though not inaccessible enough to stop poaching) of Nuevo Leon state in northeastern Mexico. The plants are quite small, averaging 1-4" diameter depending on the species. They stand out from other small globular cacti in having very unusual and attractive wrinkles covering the plant body. They grow in cracks and pockets of limestone and gypsum cliffs. They are said to prefer growing on north facing slopes, which is common for small cliff dwelling succulents of all types. Small plants eking out a living on the side of a cliff with a tiny area for roots is hard enough. Getting blasted all day by the intense desert sun in addition to that is just too much for little plants to bear.
If you were interested in Aztekium just 25 years ago, you would have thought the genus was monotypic containing just A. ritteri. So difficult to find are these plants that it wasn't until 1991 that the second species, A. hintonii was found, and it took all the way to 2013 to find and name the newest member of the genus, A. valdezii. At first glance it would be difficult to tell the species apart, but paying attention to the size of the plants, the shape and number of ribs, and details of the flowers can help you distinguish them. By contrast, Aztekium is so unique in appearance that it would be nearly impossible to mistake any other cactus for this genus.
-- Kyle Williams
Photos in Cactus Chronicle:
Aztekium ritteri, Aztekium valdezii in habitat
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PLANT OF THE MONTH Library page 1
serves as a reference library of descriptions of cactus and succulent plants
designated as Plant-of-the-Month genera in the Cactus Chronicle newsletter.
This section will grow as the web master adds information on past and current POM selections.
