Opuntia Blog

Espostoa lanata, in habitat, photo by Craig Howe

Espostoa lanata is a columnar cactus with “lanate” stems. Lanate is another word for downy or hairy. Mature plants form a cephalium on one side of the stem; thus, they bloom only from the cephalium and only at night. The fuzzy-hairy nature of the stems accounts for the common name of the cactus, “Peru old man.”

The plant in the image was photographed in habitat, in Peru, by Craig Howe. You can buy seeds or small plants of E. lanata from Mesa Garden. You can find more images of E. lanata on this page, and you can read about E. lanata here.

Melocactus peruvianus with cephalium, photo by Craig Howe

Some cacti have juvenile and adult growth, two distinct forms. Only adult growth can flower. The adult growth forms a cephalium, a very distinct region of the shoot, or an entire portion of the shoot. The cephalium is the adult growth that can flower.

Melocactus peruvianus is on type of cactus that has juvenile and adult growth forms. The cephalium of M. peruvianus is distinctive and forms after years of juvenile growth.

“Cephalium is a, frequently brightly coloured, structure of wool and bristle at the growing tip of certain cacti. It is most commonly found on cacti of the genus Melocactus and can take a number of colours, forms and shapes.”

Echinopsis in flower, image from Wikimedia

Echinopsis is generally an easy genus; the plants are not too demanding as cacti and even tolerate a windowsill in some situations–blooming when the time is right. The plants have been grown in Europe for over 150 years and part of their popularity resides in their ease of culture, but part also derives from their huge flowers.

Eventually, the fascination spread across the sea and Harry Johnson from California created the Paramount hybrids, terrific plants with large flowers and lots of color. Later hobbyists in Germany and Czechoslovakia also created hybrids.

Mr. Bob Schick used the Paramount hybrids (and other influences) to create the Schick hybrids. Eventually the Huntington Botanical Gardens introduced (through the International Succulent Introductions) over 100 Echinopsis Schick hybrids.

You can learn more about Echinopsis here, and here. You can buy the Schick hybrids from Huntington Botanical Gardens, or you may buy other great Echinopsis plants from Miles’ to Go Nursery.

Lovivia aruea (a.k.a. Echinopsis aurea), image from Wikimedia

Echinopsis is apparently the big winner it the effort to combine several genera. Lobivia and Trichoereus have been combined into (by some authors, somewhere) Echinopsis. You can find the current treatment reflected in Anderson’s book (The Cactus Family, 2001, Timber Press).

Thus, Lobivia aurea or Lobivia ferox, are now referred to by many folks as Echinopsis aurea or Echinopsis ferox, respectively. Similarly, Trichocereus bruchii is now Echinopsis bruchii.

But, when you go to buy seeds you’ll often find the plants listed under their traditional names (including plants formerly in the genus Acanthocalycium).

Thus, even though current thinking suggests that “Lobivia” doesn’t exist any longer (except as a mistake of history), you can order Lobivia seeds from SuccSeed Cactus Nursery in Sweden or from Mesa Garden in New Mexico. You can order Lobivia plants from Miles’ to Go Nursery too! Nevertheless, you’d best check for Echinopsis ferox if you want Lobivia ferox, there is no “rule” for nurseries to use one name or another and you should shop wisely lest you miss the plants you are looking for.

These are generally all (Echinopsis, Trichocereus, Lobivia, Acanthocalycium) great plants to grow, easy enough as cacti go, and typically with large showy flowers.

Lobivia winteriana (a.k.a. Echinopsis backbergii)

Wikipedia reports that:

Hecktia species or hybrid, image from Wikipedia

“Hechtia is a genus of the botanical family Bromeliaceae, subfamily Pitcairnioideae. The genus is named for Julius Gottfried Conrad Hecht, German counselor to the King of Prussia. The plants of this genus are [generally]  dioecious.”

The plants related to pineapple plants, which are also members of the Bromeliaceae. The plants are not particularly cold hardy, but H. texensis typically survived overnight frosts of 22 F in my Houston-area garden and never seemed to suffer. H. texensis is a species of north Mexico and west/south Texas (Big Bend region).

The plants appreciate excellent drainage and can be grown with cacti, but in a flower pot they will accept water for a longer period than many strictly desert cacti, even enduring the year-round rains of eastern Texas. Varieties with serrated leaves can be vicious but beautiful.

Some nurseries are more than nurseries; they actually serve as botanic gardens for their area. Plantasia Cactus Gardens doesn’t have a Web site, but they could. Lamar Orton sent me a few photos of the nursery, and it really is a botanic display garden. He reported in an email:

“We have a five acre botanic garden which emphasizes drought tolerant plants.  We are at the northern edge of the Great Basin Desert with an annual precipitation of about 10″, most falling in winter and in early spring…We have an estimated 125-150 species and varieties of cacti, plus 23 species and varieties of yuccas, including about 20 Joshua trees.  There are many other drought tolerant plants in the garden such as ice plants from South Africa, penstemons, salvias, agaves, sagebrushes, Indian paint brushes, desert willows, sedums, to name a few.  We also have many Idaho native plants and have recently contracted with the Sawtooth National Forest to establish a bed of Idaho native buckwheats (Eriogonum).”

You can check out the Plantasia price list, but remember that this is early December 2009, and prices and stock will fluctuate over time. They have lots of Opuntia, Cylindropuntia, and Corynopuntia listed, and many other plants. The nursery is located in Twin Falls, ID.

Plantasia Cactus Gardens, Twin Falls, ID

Mesa Garden is the most comprehensive cactus and succulent seed source that I know if, in the world. There are some other nurseries that have wonderful and impressive succulent seed offerings (eg, Silverhill Seeds in Africa, Australian Succulents in Australia), but Mesa Garden is the place to beat for cacti. Mesa Garden has an extensive offering of South American cacti.

Mesa Garden offers seeds and seedlings/cuttings of hundreds of plants, mostly cacti but some other succulent groups are well represented.  The seeds are modestly priced, about a dollar a packet (sometimes less and sometimes more). A recent count found about 5 dozen Opuntia seed offerings and about that many seedling/cutting offerings. The cuttings typically cost $3 to $4.

Limited but useful cultivation and hardiness information is provided for many of the species. Overseas shipping is available.

There is a lot of good information on the Web about various hobbies. One topic that many cactus growers are interested in is grafting–this is a great method for those of us who live in no-so-idea for cactus climates. 

Opuntia humifusa graft

One page I’ve enjoyed reading is called Grafting on Opuntia compressa; it is provided by the Cactus Art Nursery. They offer a great series of photos showing how to use Opuntia compressa (= O. humifusa) as a root stock. It is an informative, well done page. Opuntia compressa is an excellent rootstock because it tolerates cold and wetness with ease.

The Cactus and Succulent Society of Israel also has a Web page on grafting.

Another source for information is from the Journal of the Professional Association of Cactus Development. The article is clear and easy to read; it is called “Cactus Grafting Methods.”

Rhipsalis cereuscula, image from Wikimedia

Now, I’ve gotten my nights and weekends back, and I’m ready to start growing cacti and succulents. My friend, Tiki Mike, who lives in Houston, TX has agreed to send me some cuttings of Rhipsalis. I’ve always enjoyed this carefree, hanging-basket-type cactus, but never grew a lot of species when I lived in frosty areas 50 miles north of Houston. Now, I’m ready to try a few plants indoors, over winter.

I’m confident they’s enjoy the temperatures on my patio from the beginning of April through October, if I can just get them through the winter indoors. Rhipsalis are not known for spectacular flowers, and are probably suited for milder climates such as the coast of California, or parts of Australia.

I don’t know what types of Rhipsalis Mike is sending me, but he will send cuttings of his various garden plants. He’s agreed to dust them with a bit of rooting hormone and I’ll put them in a cool east window in small soil pots. Perhaps they’ll root easily (as is their reputation), and I’ll have happy plants to put out by Spring.

Folks who sell things always have to market; there is a “Christmas” cactus, and an “Easter” cactus, and I wondered if there as such a thing as a “Thanksgiving” cactus. Thanksgiving is coming up in a week or two.

Thanksgiving cactus, image from Wikipedia

I Googled “thanksgiving cactus” and was only mildly surprised to find that there is indeed such a thing as a Thanksgiving cactus. And it blooms about a month or two before Christmas. S. truncata is related to the “real” Christmas cactus, which I guess is a hybrid of S. truncata and something else. The two plants resemble each other, but of course the Thanksgiving cactus blooms earlier in the year.

S. truncata is a native of Brazil where is typically grows as an epiphyte. It is one of those plants that just might make a great houseplant–not needing too much water, tolerating dry air, and not needing great amounts of light. I’m only guessing, but if the two plants depend upon long nights to bloom, it would seem that the Christmas cactus needs slightly longer nights than the Thanksgiving cactus.

Schlumbergera used to be called Zygocactus, and it has been cultivated for 100-200 years (hybridized too). It may be that there is no true S. truncata out there in floritsts’ shops–perhaps all the holiday cacti for Fall are hybrids. Who knows!

The Catalog of Botanical Illustrations (Cactaceae section; Deptartment of Botany, Smithsonian Institution) is remarkable and worth a visit. There are multiple images of various Opuntia species, including two drawings of O. drummondii (O. pusilla). The drawing of O. fragilis is perfect in every detail.

The only criticism (perhaps a mild criticism) I have is that the images are size

Opuntia kleiniae, Smithsonian Institution

 restricted. Images that were originally 11 x 7 inches pop up on my screen about half that size. But, I guess you can’t have everything.

Opuntia anacantha, Argentina, photo by Willy Smith 2009

I had never heard of Opuntia anacantha before Willy Smith sent me a photo. Then I looked up the plant and the image is almost exactly as in Volume 1 of the Cactaceae by Britton and Rose (1919) on page 110.

Opuntia anacantha, The Cactaceae, Vol 1, Britton and Rose, page 110

Opuntia can be very difficult to identify, but in this case there seems to be no mistaking the linear cladodes with the fruits clustered along the distal half of the pad.  

The Britton and Rose volumes are truly amazing.

I don’t know the growth conditions for most of the South American opuntiads. I’ll just assume they don’t like too much water, and tolerate a bit of cold, unless I find out differently.

Not every succulent is a cactus; and some noncactus succulents are superb garden plants. One of these great plants is Sempervivum (hen and chicks). I was unable to grow these plants along the Gulf Coast of Texas because they always failed in summer, the victim of one sort of fungal infection or another. However, they are great plants for the mid-Atlantic states.

Sempervivum 'Centennial', image from Wikipedia

 There must be hundreds of different cultivars or Sempervivum, perhaps thousands; it seems like no one really knows because new plants are being introduced all the time. One nursery that sells many types is Squaw Mountain Gardens, in Oregon.

 One of the best things about Sempervivum is that the plants can have fantastic winter colors: multiple greens, pinks, various reds, green-blues, blues, purples, near-blacks, and grays. Then, of course, they can mix the colors and a single cultivar might have shades of pink, red, and blue in winter. Unfortunately, I haven’t found any that keep their best color in the warmer months.

 Sempervivums have fantastic shapes, a spiral of leaves surrounding a central growing point. The various rosettes are surrounded by other rosettes that are larger, or smaller, depending upon relative age. Often, when a rosette blooms (they are not known for spectacular flowers), it will die, but the empty area is often quickly filled in by ever expanding neighbor rosettes.  Aracnoidium types (spider web types) have a filament of gray fuzz over the leaves, giving them a nice look. 

Sempervivum arachnoideum, image from Wikipedia

There is not a lot of information on the WWW about Tacinga, an opuntiad from South America, but there is some. The best part about this genus is the tubular flowers that call to bird.

• Cactus Art Nurseryhas a nice page on Tacinga.
• Desert Tropicals provides a bit of information.
• Some great photos of flowers can be found at O Paraiso.

In addition to the Web, there is a new article from the Cactus and Succulent Journal (81[3]:156-161. 2009).

Tacinga flowers, photo from Wikimedia commons

• Opuntia
• Brasilopuntia and Cylindropuntia
• Austrocylindropuntia, Cylindropuntia, and Miqueliopuntia
• Cumulopuntia, Grusonia, Tephrocactus

Tephrocactus articulata, photo by Barrie Glover

There is a great old book called “The Systematic Anatomy of the Dicotyledons” that has a great chapter on the Cactaceae.  I was lucky enough to find the book on Google Books and have extracted the Cactaceae portion.

There are great drawings of cactus epidermis, cactus wood cells, and Opuntia spines. There is a fair discussion of Opuntia in general and the chapter is a nice read.

The Systematic Anatomy of the Cactaceae (ie, Docotyledons), H. Solereder, Vol. I, Clarendon Press (Oxford), 1908. The cactus portion of the extracted pages starts on page 9.

Opuntia macrocentra flower, plant from Alamogordo, NM, photo by Dave Ferguson

This amazing library is only possible because of the Internet. They have nice collection of digitized books online, mostly the books are older or the author has provided permission to reproduce the books.

There are some Opuntia/Opuntiodeae nuggets in the collection. For instance, try the Tephrocactus and other prickly pears by Michael KeiBling (a book mentioned by a contributor to this blog, Ian Menkins). You can read the book online, or you can download the entire book as a printable PDF file. The images are worth the read, and for those of you interested in cold-hardy cacti, there is a long listing of plants from the Big Bend area.

There is even a copy of Del Weniger’s book, Cacti of Texas and neighboring states. This colorful book describes a number of Texas cacti, including O. leptocarpa, which is a plant apparently forgotten by modern botanists.

Del Weniger's book, from the Cactus and Succulent Image Gallery

Northern Nursery (in Denmark) has nice photos of various Opuntiodeae.  They have some of the best images on the Web of Opuntia debrechyzi and Opuntia chisoensis. Many of the cacti at Northern Nursery are cold hardy.

If you want a quick view of the two species, you can click on the thumbnail images below. However, you can find more images by Martin Ravn Tversted at this link: Northern Nursery. 

Opuntia debrechzyi, photo from Northern NurseryOpuntia chisoensis, photo by Martin Ravn Tversted

Opuntia chisoensis, photo by Northern Nursery

Willy Smith’s Web site is unassuming if you happen in via the front page. But don’t let that fool you, Willy has a wealth of information in images and location maps. The power of his Web site will keep you coming back to view images of plants.  He has habitat shots, as well as photos of his hobby plants. 

 Willy provides habitat images of seven different genera in the Opuntiodeae: Austrocylindropuntia, Opuntia, Pereskiopsis, Pterocactus, Tephrocactus, Maihueniopsis, and Tunilla.

 Willy provides nice field images of multiple Opuntia species of his country (Argentina). These are Opuntia anacantha,O. cordobensis,O. cardiosperma,O. elata,O. paraguayensis,O. penicilligra,O. quimilo,O. salmiana,O. schickendantzii,and O. sulphurea.

 In addition to loving cacti and helping us by providing information and photos, Willy organizes cactus tours of his part of the world. Check out his tour page below if you want to know more. 

• Link: Argentine Cacti
• Link: Cactus Tours

Opuntia basilaris is the archetypal “beaver-tail” opuntia. It’s pads are spineless and sometimes nearly elliptical (or triangular), suggesting the flat tail of a beaver.

Opuntia basilaris

O. basilaris is commonly found in the Mojave Desert, especially between 2,000 and 4,000 feet in elevation. However, I have observed plants growing over 5,000 feet in elevation near Las Vegas, NV on Mountains to the west (Mt. Potosi, Mt. Charleston), and near Beatty, NV. Such locations are nominally USDA climate zone 8 (or thereabouts). However, at 5,000 feet elevation, the plants must surely experience occasional very cold temperatures, perhaps as low as -10 F or colder.

Opuntia basilaris

Opuntia valida is a wonderfully spiny plant with 4 to 8 stout spines splayed out from the dark areoles. The plants may make a short bush, or they may spread out along the ground. Pads are large, perhaps 7 inches wide and up to 11 inches long.

Opuntia valida, Kingman, AZ

The plant seems to grow mostly in zone 7 in New Mexico and Arizona, and can be found at 5,000 feet elevation in the general vicinity of Albuquerque, NM.

Click to go to the Opuntia valida Web page.

Don’t confuse O. valida with O. engelmanii. Half-a-dozen large opuntia with yellow flowers are lumped into various categories (O. engelmannii is just one), but they are separate entities and distiguisable by various traits. O. valida is, after a bit of study, easily differentiated from O. engelmannii.

Opuntia valida

Opuntia engelmanii (O. gregoriana type)

Some Opuntia (and opuntiads) tolerate year-round rain as long as they have reasonable drainage. These may, or may not be cold hardy. In general, the plants on the list (below) grow from central Texas to Florida, and experience long rainy spells from time to time in their natural habitats.

Opuntia alta, south Texas (near Zapata), moisture tolerant, photo by Mike Burnett

For instance, Nopalea cochenillifera is easily grown in many gardens that don’t experience frost; it doesnpt matter if they grow in Florida (with year-round rains) or in California (with winter rains).  

These plants can tolerate year-round moisture, as defined by Houston, TX rains. They may, or may not, be cold hardy.

The photo is provided by Mike Burnett, a talented plant photographer and naturalist.

Preliminary List of Moisture-tolerant Opuntiads

1. Nopalea spp.
2. Ophuntia humifusa
3. Opuntia alta
4. Opuntia ammophila
5. Opuntia anahuacensis
6. Opuntia bentonii
7. Opuntia cacanapa
8. Opuntia davisii
9. Opuntia dillenii
10. Opuntia fragilis
11. Opuntia gilvescens
12. Opuntia imbricata
13. Opuntia kleiniae
14. Opuntia leptocarpa
15. Opuntia leptocaulis
16. Opuntia lindheimeri
17. Opuntia macrorhiza
18. Opuntia nitens
19. Opuntia orbiculata
20. Opuntia polyacantha
21. Opuntia pusilla
22. Opuntia pyrocarpa
23. Opuntia sanguinicola
24. Opuntia stricta
25. Opuntia turbinata

Opuntia gilvescens in bud

The first time I encountered Opuntia gilvescens was in south-central Oklahoma, along Interstate 35 near Ardmore, OK. The plants were growing in rocky outcrops adjacent to the highway with O. orbiculata and Echinocereus reichenbachii. I took photos and was able to identify the O. gilvescens plants with help from a “cactus” friend.

 O. gilvescens is apparently, almost always misidentified as O. phaecantha, like so many medium-sized Opuntia. But, O. gilvescens is distinctive in appearance. I’ve found it at 4,000 to 5,500 feet in central Arizona (near Bagdad), at 5,000 feet just west of Las Vegas, Nevada (Mt. Potosi).

Click to access the Opuntia gilvescens Web page.

Opuntia gilvescens

Opuntia orbiculata is very cold-hardy, growing into north Texas and southern Oklahoma

I looked through the list of Opuntia species that I have grown, or that I have encountered, and I think there are over four dozen that can be classified as at least “moderately cold hardy.” For me, moderately cold hardy means that the plants will likely survive 10 F, if properly acclimated to the cold and not too wet.

 Wetness is typically a factor in cold hardiness; plants that are too wet in the winter and spring can rot, even if they are able to tolerate the cold under optimum (dry) conditions.  Thus, I can think of three different lists to put together: 1) cold-hardy plants, 2) moisture-tolerant plants, and 3) cold-hardy and moisture-tolerant plants. Of course, there is a fourth list that is possible: plants that are cold-hardy to -10 F. (Note: 10 F corresponds to -12 C;  -10 F corresponds to -23 C).

The list below contains those plants that I think are intrinsically cold hardy when they experience typical (ie, natural) growing conditions. The list doesn’t contain plants I think might be “iffy” or Cylindropuntia spp. This list contains many species that will be cold hardy to 0 F, -10 F, or even colder.  For another list try Benny’s Kaktus list. 

 Preliminary List of Cold-hardy Opuntias

1. Opuntia angustata
2. Opuntia arenaria
3. Opuntia atrispina
4. Opuntia aurea
5. Opuntia aureispina     
6. Opuntia azurea           
7. Opuntia basilaris
8. Opuntia cacanapa       
9. Opuntia camanchica
10. Opuntia charlestonensis
11. Opuntia chisosensis    
12. Opuntia chlorotica
13. Opuntia confusa 
14. Opuntia curovspina 
15. Opuntia cymochila
16. Opuntia cyclodes
17. Opuntia debreczyi
18. Opuntia dillei             
19. Opuntia dulcis
20. Opuntia engelmannii
21. Opuntia erinacea        
22. Opuntia flavispina      
23. Opuntia fragilis
24. Opuntia gilvescens
25. Opuntia gregoriana
26. Opuntia humifusa
27. Opuntia leptocarpa
28. Opuntia lindheimeri
29. Opuntia mackensenii
30. Opuntia macrocentra
31. Opuntia macrorhiza
32. Opuntia martiniana
33. Opuntia microcarpa    
34. Opuntia nicholii 
35. Opuntia orbiculata
36. Opuntia phaeacantha    
37. Opuntia polyacantha  
38. Opuntia polyacantha  
39. Opuntia polyacantha
40. Opuntia pottsii
41. Opuntia pyrocarpa
42. Opuntia robusta
43. Opuntia sanguinicola
44. Opuntia santa-rita
45. Opuntia spinosibacca
46. Opuntia strigil
47. Opuntia tortispina
48. Opuntia trichophora 
49. Opuntia valida 
50. Opuntia woodsii
51. Opuntia wootonii
52. Opuntia zuniensis

I like putting images into blog posts. But, one problem with blogs is that blog format (in the templates I’ve used) is limited half a web page or a bit more. So, images need to be fairly small (400 to 600 pixels across, maximum) or they won’t fit into the allotted space. I guess that I could put links to larger images in place, but that would sort of detract from the blog topic. The best solution I have for now is to presize images and store them in a special directory on my computer, or online. Then, I can upload them or call the URL address. 

Opuntia cacanapa var. Ellisiana

I’m using a handy bit of freeware called “Easy Thumbnails,” from Fookes. The software permits easy resizing of one, or hundreds of images. It will save the images in different output formats, and will even rename the images that it creates. Even as I write these few paragraphs, I’ve got the software resizing about 2,000 images so that I can choose among them for inclusion in the blog.

I think, but am not 100% sure, that if I post images here at blogger.com I will lose copyright to the images. Perhaps the solution is to use small images for the blog, and use large images for the opuntiads Web site .