Opuntia Blog

Opuntia fosbergii, photo copyright Gary Monroe

Cylindropuntia xfosbergii (Opuntia fosbergii) is treated as a naturally occurring hybrid by the Flora of North America, rather than a distinct species (C. fosbergii = C. bigelovii × C. echinocarpa). At one time is was considered to be a type of C. bigelovii (Opuntia bigelovii var. hoffmannii).

Chollas (ie, cylindropuntia) are difficult to study for several reasons: they grow in inhospitable areas, they are incredibly spiny, they often resemble each other, and they sometimes hybridize. You can read more about chollas here, and here.

If you live in the warmer southwest, C. fosbergii is a striking garden plant to grow, but I don’t know where you could purchase the plant. It might be protected.

Austrocylindropuntia vestita, photo by Craig Howe

Austrocylindropuntia are opuntiads from South America with cylindrical stems. For many years these plants were classified as Opuntia, but modern taxonomy places them in their own genus (that is related to Opuntia).

Austrocylindropuntia vestita is from Bolivia or northern Argenina. It is not particularly cold-hardy, but it has bright red flowers that are charming. The plants that I have observed were not large (under 2-foot-tall), and they were much branched at the base.

Apparently Austrocylindropuntia vestitia as had several names over the years, including: Opuntia vestita, Opuntia heteromorpha, Austrocylindropuntia chuquisacana, Opuntia chuquisacana, and Cylindropuntia vestita.

Austrocylindropuntia subulata, long leaves showing, click on photo for original large image at Flickr

Austrocylindropuntia subulata gows at high elevations in Peru and Ecuador, from 9,000 to 12,500 ft. Probably for this reason the plant has proven relatively cold hardy for me. It easily survived 16 F, and I think it would have taken 10 F in stride. Additionally, A. subulata was a stellar performer in Texas, even when it got year round rain.

A. subulata is reported to be a large plant in the wild, tree like. I never had a plant reach tree-like proportions, but I kept it in a relatively small 8″ pot and had to prune it back once year.

The interesting thing about A. subulata is that it holds its leaves a long time, and the leaves are large for an opuntiad. The leaves will drop if the plant is stressed for water. However; on winter I left the plant sitting in a sunny location that was sheltered from the rain, and the leaves on the top half of the plant stayed all winter.

The flowers are red orange, but my plant never flowered. Maybe I should have planted it in the ground and let it get tall.

You can read more about A. subulata here, and here.

Opuntia echinocarpa, photo from Wikimedia

Opuntia echinocarpa (Cylindropuntia echinocarpa) is a Mojave Desert plant that grows at lower elevations (perhaps, 2,000 feet to 5,000 ft). In some places it is very common, almost as common as creosote bush (Larryea tridentata).

The flowers of O. echinocarpa are greenish, sometimes tinged with brown or russet; like many Cylindropuntia flowers they are not nearly as showy as other Opuntia flowers. The name “echinocarpa” means “spiny fruit,” and sure enough the fruits of this species are very spiny. Once I tried to collect a few seeds and I needed pliers just to break open the stiff fruits, but even though I used pliers I still got half-a-dozen sticks in my fingers and hands.

O. echinocarpa is more tolerant of too much water than O. basilaris, but neither plant enjoys much summer rain. And O. echinocarpa is probably hardy to -5 F (or perhaps zero F); maybe the plants from 5,000 feet are hardy another 10 degrees F.

You can read more about O. echinocarpa here, and here. You can buy seeds of O. echinocarpa from Mesa Garden.

Austrocylindropuntia exaltata

At first look you might wonder if Austrocylindropuntia exaltata is related to Cylindropuntia imbricata, but these two opuntiads are not closely related. The first one is found in South America (in Peru and Chile) and the second one is found in North America.

A. exaltata has nice red flowers and can be found near the equator growing up to 10,000 ft elevation, or higher. C. imbricata has magenta flowers and grows from 1,000 ft to about 6,000 feet in Texas and New Mexico (and Mexico).

I’ve never grown A. exaltata, but C. imbricata is a bullet-tough plant that withstands cold, too much water, and searing heat. Both can be expected to take up a fair bit of space in the garden as the grow tall and semi-wide.

Small Opuntia whipplei, Kingman, AZ

Opuntia whipplei may make short plants (under a foot tall), or it may form plant over 4-foot-tall. The species has a lot of variation in size. Additionally, the species is found over a large range: from the southern tip of Nevada, across northern Arizona, all the way to northwestern New Mexico, and into adjacent portions of Utah and Colorado. It is a durable and easy-to-care-for plant, tolerating more water than many cacti.

O. whipplei is a Cylindropuntia, so it has longish, cylindrical cladodes, rather than the flat, pancake-like cladodes of “real” Opuntia. Hybrids between Opuntia whipplei and O. imbricata have been reported; these tend to have greenish-purple (or green) flowers. Additionally, O. whipplei is reported (by the Flora of North America) to hybridize with O. leptocaulis. The species and the hybrids are wonderfully hardy, easily taking -10 F, and perhaps colder.

It is reported that O. multigeniculata is a hybrid between O. whipplei and O. echinocarpa, but as near as I can tell, O. geniculata is now a “real” species no matter its origins.

Close-up of Opuntia whipplei cladode

Cactus wren, image from Wikimedia

The cactus wren is found in the Mojave, Sonora, and Chihuahua Deserts; the wren may be found in southern California, Nevada, or Arizona, and deep into Mexico. The bird is easily observed flitting about the desert in search of insects, and its nests may be found in various large cacti including chollas (Cylindropuntia), saguaro (in holes), and some other columnar or barrel cacti. Or, sometimes the plant will nest in yucca plants.

 Males and females resemble each other, and both search for ants, beetles, grasshoppers, and bees, etc, though they might eat a bit of fruit now and then or seeds. The birds are remarkably efficient at extracting water from their prey, and they seldom need to drink. The white eye stripe and the black breast spots are useful for identification; there is no other bird like it.

I’ve seen this bird throughout the Mojave desert, but irregularly so. The nests are hard to miss, often a scramble of twigs (with a roof and “tunnel” entry) in a large cholla or perhaps a Joshua tree.

Cactus wren nest in Opuntia acanthodes, Kingman, AZ

There are a number of Cylidropuntia species in Texas; they tend to be sturdy, tolerant of too much water, and cold-hardy. Opuntia davisii is found in western Texas and in eastern New Mexico. Curtis’s Botanical Magazine wrote in 1882 that O. davisii is:  

“A small shrubby species, remarkable for the bronzy color of the flowers, which have a peculiar metallic lustre…O. davisii is a native of the district of New Mexico, eastward and westward of the Tucamcari Hills…on the head waters of the Canadian River, a branch of the Arkansas.”

Opuntia davisii, photo from Gary Nored, click for original at Flickr

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

Opuntia multigeniculata, northern Arizona

Opuntia multigeniculata has been variously described as a stable species, a hybrid between O. whipplei and O. echinocarpa, or even as a variety of O. whipplei. I think the general consensus now is that it is a stable species that is found  infrequently, but regularly, in southern Nevada and northwestern Arizona. The common name is the blue diamond cholla, perhaps in reference to Blue Diamond Rd. south of Las Vegas (just a guess).

There is good Web coverage for such an uncommon Opuntia; the State of Nevada has published a monograph about O. multigeniculata; one Web site (Vegetation Around Las Vegas) provides nice habitat photos; and an environmental report is available.

Opuntia multigeniculata is an uncommon cylindropuntia that occurs in sporadic areas of the Mojave Desert, up to 4,000 or 5,000 ft. As such, it should easily survive temperatures to zero F (-18 C). It might be able to withstand even colder temperatures. The problem for hobbyists is that the plant is apparently not in commerce.

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.