Fragile prickly pear, Opuntia fragilis (Nutt.) Haw, reaches its northern limit in British Columbia and Alberta at 58 degrees N. At this latitude the species apparently grows well, flowers, fruits, and produces viable seed according to Dr. Eric Ribbens.
I have observed O. fragilis on Vancouver Island near Victoria. The plant grows in a few locations up-island and on the Gulf Islands. These areas experience long periods of freezing. The cacti adapt to such conditions by several poorly understood mechanisms: 1) changes in water content and osmotic pressure, 2) a gradual loss of water beginning in Fall, and 3) possibly other unknown mechanisms. The overall result it that the plants gradually lose internal water in Fall and shrivel, only to rehydrate and swell in Spring (Cota-Sanches, Hazeltonia, 2002, 9:17-25).
Although the species is not listed as endangered, it has experienced reduction in its distribution by pressure from agriculture and urban development in most areas of the island. Plants I have cultivated have not flowered; however, another gardener reports that her plants flowered after 7 years in the garden. The flowers are a delicate yellow, sometimes with a gentle reddish center. Plants may have 100+ cladodes in habitat where it seems to propagate only by asexual means. The fiercely barbed cladodes are distributed by water, wind, humans, and animals.
Added note: O. fragilis was first collected from Vancouver Island by Archibald Menzies who reported the species from the Gulf Islands in May 1792,
He was a little surprised to meet with the Cactus Opuntia thus far northward, it grew plentifully but in a very dwarf state on the eastern point of the island which is low flat and dry sandy soil (cited in Clark, 1976).
as reported by Pojar and MacKinnon (Plants of the Pacific Northwest Coast, Lone Line Publishing, 1994).
1. Ribbens, Eric. Opuntia fragilis, Taxonomy, Distribution, and Ecology. Hasseltonia 14:94-110. 2007.
2. Menzies' Journal of Vancouver' voyages April october 1792.
Edited with Botanical and Ethnological notes by C.F. Newcombe, M.D. and a biographical note by J. Forsyth.
printed by Authority of the Legislative Assembly, Victoria B.C.
3. Pojar, Jim, and MacKinnon, Andy. Plants of Coastal British Columbia. 1994. B.C. Ministery of Forests and Lone Pine Publishing