Our next-door neighbor in Salt Lake City had a whole border of them. In spring a nice show of tulips would pop up between the flattened cacti, then they'd grow up nicely to cover the tulip foliage. She even used to get a harvest of prickly pears some years, and would make little jars of jelly to give out for the holidays. It's very good.
Coolest thing to me was when I asked her how the heck she weeded that prickly border, and she said "oh, Roundup. It kills the weeds but not the cacti."
(this was 15 years ago. I'm sure she doesn't use Roundup any more.)
