This cactus is native to parts of Ontario, and we've had one in the rockery area of the Backyard Garden for many years. Although it looks shriveled and dead in early spring, it always fills out (and fills up with water) and turns green by this time of year. It has a lovely light yellow flower that lasts only a few days. (Sandy)

There has been a small stand of this species, naturally occurring as far as is known, about two hours west of Ottawa. (Christine)