Cal- I think it nicely catches the feel of the desert, especially the brief bloom after the long-awaited rain. I agree with Shanna about the "Oblivious to dry and heat". First, I don't like the parallelism of dry-heat, since one is an adjective and one a noun. I would change dry to drought, except that you've used that two lines up. Perhaps changing heat to hot? Of course, your poetic license clearly entitles you to use dry as a noun if you want. Second, I don't agree with the sense of cacti being oblivious to the dry and hot. I would be more comfortable with them being at peace with it, or relishing it, or even withstanding or resisting it, but not being oblivious. My last comment for now would be that I don't feel any rhythm as I read it, which would make it stronger IMHO.