Hi Valygirl,

I have either smoke trees or bushes - bushes I think - and they are doing fine without fertizing. I have to admit, however, that I am lousy at fertilizing. I always forget!
I'm in Colorado Springs, so our temps do not get quite as high as yours. I love my smoke bushes!,

I have one - I mulch it with grass clippings, which deteriorate at about the right rate to keep the plant growing nicely.

They take a good three years just sitting there building roots, then they take off the 3rd year.

I have two smokebushes. I spray them a couple of times each year with fish emulsion when I spray my garden. But I think they would do fine without it. Three times a year sounds like overkill to me.