I've never done any sort of spraying for my fruit trees. Well, the first year the apple tree got blight, and I cut it back below the blight and covered it with whatever it was that my Western Gardening book recommended. But nothing else. I have dusted the grapes with sevin and some ornamental plants that had bugs of one sort or another, but never the fruit trees. The grapefrut tree is huge, as is the pear (some sort of asian pear, supposedly). The strawberry guava is still small, but produced a fair amount of fruits last year, the pomegranite had tons. Nectarine, plum and apricot are still too new, although I did get a couple of plums. The lemon tree (improved meyer--YUM!) had tons of huge lemons.
Alternatively, dig a few shovelfuls every day for a week and you will have your hole.
