Many people don’t realize that there are a good number of cactus varieties that are fully hardy in Alberta. With gardeners becoming more and more conscious of how much water they are using to keep their plants healthy, drought-tolerant plants are more popular than ever, and cacti fit that bill better than anything! Not only do cacti contribute a unique and rugged look to a landscape from their foliage, but they actually have some of the showiest flowers among perennials. Blooming for several weeks in the summer, they will reward very little effort with a disproportionate amount of color!
To grow hardy cacti successfully, plant in a sunny, hot and dry location. A sandy and very free-draining soil mix is recommended; 60% garden soil and 40% sand works well. Raised beds are a great way to ensure the plants get the drainage they need, as the easiest way to kill them is to rot them out! There is no need to water your cacti unless they go for several weeks during the hottest part of the summer with no rain.
Three species of cacti are native to Alberta. The two prickly pear species are the most common, and most of our selections are derived from these. Both are extremely hardy, being found throughout the province. Fragile prickly pear (Opuntia fragilis) is found as far north as Peace River Country! These cacti get their name from the edible fruit they produce, which is sweet but covered in prickly skin.
Following are some cultivars available at Greenland which are fully hardy in Alberta, all worth trying:
Plains Prickly Pear (Opuntia polyacantha)
The most common species, found throughout Alberta but especially near Medicine Hat. The typical form creates a slowly spreading patch of flat, spiny pads up to 8-12” tall and 2-3 feet wide. It produces bright yellow flowers.
‘Purple Desert’ Prickly Pear (Opuntia polyacantha ‘Purple Desert’)
A special selection of prickly pear, this has intense pink flowers with a yellow center and stunning purple-tinged pads.
‘Namao Rose’ Prickly Pear (Opuntia polyacantha ‘Namao Rose’)
A local selection from just northeast of Edmonton. Smaller growth habit and bright pink flowers with yellow centers. Joe’s favorite! Ht. 6” Sp. 12”
‘Bulbispina’ Prickly Pear (Opuntia polyacantha ‘Bulbispina’)
A unique selection with more upright, slightly cylindrical pads and showy pink flowers. Ht. 12” Sp. 18”
Fragile Prickly Pear (Opuntia fragilis)
This native Albertan species earns its name from the fact that the pads are so fragile they can break off when they stick to animal hair or clothes. When deposited elsewhere on the ground, they will take root and form a new plant; this is one way the plant propagates itself! These are shorter plants that tend to produce more dense patches compared to the plains prickly pear. Typically yellow-flowered, we are offering the pink-flowered form this year. Ht. 4” Sp. 12”
‘Pony’ Fragile Prickly Pear (Opuntia fragilis ‘Pony’)
A local selection found at the Devonian Botanic Garden. Large, rich magenta-pink flowers with yellow centers. Ht. 4” Sp. 12”
‘Alberta Sunset’ Fragile Prickly Pear (Opuntia fragilis ‘Alberta Sunset’)
Outstanding local selection with nearly red flowers and nearly spineless pads! Ht. 6” Sp. 12”
‘Bronze Beauty’ Fragile Prickly Pear (Opuntia fragilis ‘Bronze Beauty’)
This very nice cultivar has yellow flowers that mature to a gorgeous bronzy color. It is also nearly spineless and has cute, slightly rounded pads. Ht. 4” Sp. 12”
Brittle Prickly Pear (Opuntia fragilis var. denudata)
A cute form of fragile prickly pear that produces rounded pads with short, hair-like spines that are not sharp. This is a low-growing cactus with yellow flowers. Ht. 3” Sp. 12”
Hybrid Prickly Pear (Opuntia polyacantha x fragilis)
A low-growing and very hardy hybrid between both of our native species. Available in both pink- and yellow-flowered forms. Ht. 4” Sp. 12”
Eastern Prickly Pear (Opuntia humifusa)
This species can be found in eastern Canada and is fully hardy on the prairies. It is similar to plains prickly pear, with flattened pads that only produce spines towards the top, and pale yellow flowers in summer. Spreads to form a patch 6” tall and 12-18” wide.