We have horses and they eat most things without problems. Something that might look nice at an equestrian center would be deergrass. Horses do like it but ours have had no problems eating it and it is drought tolerent, evergreen, and has a lovely fountaining shape.

I suspect that the question might be better what not to put in and of course oleander would be the big no no in your area. I am trying to grow some eucalyptus in our horse area because I am looking for something that they won't eat and I think ours must be part goat because they've eaten about everything else we've tried even a very thorny texas ebony tree.

Good Luck, Maria