The eastern prickly pear, or low prickly pear, (Opuntia humifusa) is a cactus native to portions of the northeastern US and even into southwestern Ontario, Canada. In my home state of Pennsylvania, it's found on dry, rocky outcroppings like shale barrens, and sandy, hot soils. It does quite well in cultivation as well, as long as you have a hot, sunny, and well-drained spot for it. I planted several at the bottom of a west-facing slope that gets about 10 hours of full sun during the summer, and