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Opuntia are natives of North and South America, as well as the West Indies . These plants comprise the largest genus of the Cactus family with around 470 species.
Opuntias are usually fast-growing, take little care, and many are very hardy. These beautiful cacti are famous for their distinct character and are standouts as specimens. Some Opuntias are miniatures that span only inches, and are essentially groundcovers, while others are arborescent tree forms to 20' in height.
The morphologies of Opuntia are quite diversified; with jointed stems of flat paddles, cylinders or globes. This difference in morphologies has led to the creation of subsections in the Opuntia family ~ Platyopuntia, Cylindropuntia and Corynopuntia or Tephrocactus Platyopuntias have flat "paddle-shaped' pads (also known as "ears") in jointed segments. One example is Opuntia basilaris, commonly known as the "Beaver Tail". Subsection Cylindropuntia has plants with cylindrical joints. This subsection includes the "Cholla", of which perhaps the most famous, or, in truth, infamous, is the Opuntia bigelovii, known as the "Jumping Cholla" for its predilection to detach joints very easily onto passing animals or humans. This is a method of propagation, for the recipient of the detached joint will then carry it elsewhere, where eventually it will become detached, root and start a new colony. A third subsection is the Corynopuntia or Tephrocactus, usually smaller clumps of ovoid spheres or globes, only an inch or two in circumference. This group includes the well-known ‘Paper Spine", Opuntias have either spines or glochids ("polka dots" of minute spines), or a combination of both in colors of yellow, white, reddish, beige, or black emerging from woolly areoles. One exception is the ‘Burbank' Spineless, a cultivar devoid of both spines and glochids, developed as cattle fodder.The flowers of the Opuntia average 3" in diameter and are usually yellow but some are purple, orange, red or yellow with a red center.
Many of the Platyopuntias are edible (nopales or nopalitos), and for centuries have been prepared in egg dishes, or as a side veggie. The fruit is also often edible and quite sweet and has been used as a natural treat or to sweeten another dish.
Some Opuntias fall into the category of extremely cold hardy plants. One variety is Opuntia compressa, which is resistant to excessive moisture and rain and has very good cold resistance, reputed to be –30°F. Opuntia compressa is easily grown, tolerates light shade and is a good plant to grow in the colder northern climate. Other varieties that are very cold-hardy are O. arenaria, O. fragilis, O. imbricata, O. phaeacantha. O. polyacantha. It has been reported that Opuntia macrocentra has survived –45°F.
Opuntias have gained favor as landscaping or patio plants and even as houseplants. Many of us want a little piece of the desert close by and what better way to achieve this than by planting an Opuntia, icon of the "Southwest Look". In Australia , two Opuntias: Opuntia ficus-indica and Opuntia microdasys were listed as two ultimate plants for the garden.
Care and Information for Opuntias
In the spring and summer the soil should become fairly dry between waterings. The plant should be given a deep drink at this time, to the extent that the water runs out the bottom of the pot. In winter, it is best to water only enough to keep the plants from shriveling. In order for any plant to retain its cold adaptation, it is necessary to allow the plant to lose some moisture content in preparation for the cold weather; in other words, to "harden off". Plants that are bursting with water, and have been overfed with fertilizer during the year causing weak growth, are ill-equipped to handle adversely cold temperatures and are more prone to pests and pathogens.
Opuntia grow best where they receive at least 4 hours of sunlight daily, but they will grow fairly well in bright indirect light indoors (such as that reflected from white or light walls.
In general, Opuntias prefer night temperatures in the winter no less than 40°F (around 55°F is necessary for them to continue growth during the winter months). In the spring and summer, Opuntias prefer night temperatures of 65°F to 70°F and daytime temperatures of 75°F to 85°F, but can handle adversity in either direction.
Established plants should be fed once in the spring. To attain the fastest growth, repot every spring. If you prefer to control the growth of your plant to conform to space limitations, repot in the spring only when the plant has become "root-bound" or too crowded in the pot. Most Opuntias will grow well in a general-purpose cactus mix. Some Opuntias prefer soils with added lime chips or bone meal.
Your Opuntia, given just a little care, will reward you for years as your ‘Southwest Icon’.
Some Outstanding Species of Opuntia
Tree-like plants (up to 15') originating in Haiti. The flattened pads are somewhat elongated and a very dark, glossy green. The orange flowers are diurnal Opuntia falcata grows well in full sun or morning sun, and prefers a normal cactus soil. Excellent landscape plant.
Opuntia violacea ‘Santa Rita’
Native of Texas , Arizona and northern Mexico. Grows to 3' with bluish-tinged round pads. In the winter or during times of drought the pads become reddish purple. An excellent landscape plant or patio plant. Flowers are yellow with red center, diurnal, appearing in the summer.
Opuntia robusta is generally tree-like up to 15'. The pads are up to 12" across, very rounded and bluish-grey frosted with few spines. The yellow flowers are 3", diurnal and appearing in the summer. Opuntia robusta prefers bright light and normal cactus soil. This species originated in Mexico. An outstanding landscape plant.
Freely branching, tree-like opuntia reaching a maximum height of 10 to 13 feet. The pads have whitish spines. Flowers are yellow, diurnal and appear in summer. Opuntia leucotricha, from central Mexico , prefers an enriched mineral soil and lots of sun. Landscape plant or patio.
This Opuntia occurs in many forms and is very popularly used as a houseplant or patio plant. The 3" to 6" pads are thickly dotted with minute spines called
glochidia, giving the plant a "Dotted Swiss" resemblance. Slower growing (will not take over) to 3-4'. The glochids can be either white (albispina), yellow or reddish, cinnamon color (rufida). The O. microdasys v. rufida also has a miniature, monstrose form. The yellow microdasys also has a crested form, which is very beautiful with undulating waves of yellow tufted ears. The microdays flowers in summer with yellow flowers. This plant prefers slight shade or morning sun, cactus soil and originates from central Mexico .
This is a mat-forming plant with ovoid joints. Opuntia clavata likes bright sun and slightly calcereous cactus soil.
Tephrocactus turpinii or glomerata ("Paper Spine")
This is the ever-popular "Paper Spine", which has spines that have evolved into flattened, whitish papery protuberances up to 4" long from the ovoid joint. The papery-spined joints are very easily detached, sometimes even by severe wind and in this way are scattered about to root and start new colonies of "Paper Spines".
Opuntia or Austrocylindropuntia subulata
This species grows to 13', with branching cylindrical stems that have long, pale yellow spines. Reddish flowers appear in the summer. This plant requires bright light and normal cactus soil. There is also a monstrose, dwarf form of Opuntia subulata, which branches freely in the shape of a Christmas tree and has vestigial leaves, which turn pink in the cold. The dwarf form prefers morning sun and cactus soil. This Opuntia can be decorated as a miniature desert Christmas tree.
Opuntia monacantha variegata monstrose "Joseph's Coat"
This Opuntia is a dwarf of the larger "Joseph's Coat" and has plaid variegation of pink, yellowish white and green in varying patterns. Indoor or greenhouse plant; prefers morning sun and cactus soil.