Can I root prickly pear pads that I buy (presumably for food) in the grocery store? It seems like it would be a great way to get some thornless prickly pear cacti growing. If I were to do it, I would want to grow them as houseplants (or else overwinter them in the winters).
Edit: I wouldn't try this now, whether or not I would have when I asked the question. There's too much risk of patents and breaking crop laws when you attempt to grow stuff from grocery store produce (e.g. growing grocery store garlic in Idaho carries a potentially hefty penalty). I know prickly pears probably aren't the world's most patented vegetables, but I still like to avoid grocery store produce. I didn't actually try it. Plus, those pads probably aren't very cold hardy; I'd rather buy some from coldhardycactus.com, or some such.