Answer: There are several types of Opuntia, or prickly ear, cactus that are edible and used in Southwest and Mexican cuisine. Since hardiness varies, be sure the type you choose is hardy in your region. At least one variety, O. compressa, is hardy to zone 4.
You can purchase Opuntia cactus from Oregon Exotics Nursery (ph# 541-846-7578). Double check with them about the hardiness of various species. This nursery specializes in exotic fruits, nuts, and vegetables--their catalog is fascinating!
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