I planted a xeriscape garden last year & put "yum yum" mix (from High Country Gardens) in the bottom of each hole. I plan to fertilize again this fall. I'm hoping to get some guidelines, here, for fertilizers - ie. what #'s or ingredients should I look for. Should I add worm castings, alfalfa, etc.? Any suggestions are welcome. I'm planning to fertilize each fall & add compost each spring, going forward - does that make sense?