I'm growing persimmon trees for something to do in retirement. Not just 1 or 2 but 2 lots with about a hundred each in addition to peaches, plums, figs, pears and pomegranates. The first lot is about 4 years old. The second lot is just planted. We live in an area with mostly clay soil and none of the first few fruit trees grew much after a couple years. So I had a guy with a big 36-inch back hoe dig the clay out and replaced it with wood chips at the bottom, good soil, and more wood chips on the top. No fertilizing has been done yet. The first lot of persimmon trees produced a 2nd crop last year, about 2100 fruits for a hundred trees. From the number of new flowering and now little persimmons, I believe we will have 3000-4000 fruits out of a hundred trees.
Now about fruit drops and fertilizer. From what a seasoned peach farmer told me, fruit drops is natures way of dropping the fruits it cannot keep. My trees are so loaded that on some trees, a good % of fruits have already dropped. I may even have to cull out more so they will not break the smaller branches. The funny thing that is some trees have more or too many fruits and some few to none at all.
About fertilizer usage. From what I have read, any and all the suggestions contributors have made appear to have been applied and they all seem to be strong in their opinions. It appears that they all seem to work. The one that I think works the best is to look at the tree growth and color of the leaves. If they are a bit stunted and look not so healthy green, a small amount of balanced fertilizer is in order. It's experimental. The reason is simple. The nature of the soil in each location, annual supply of sun and rain and the shade from surrounding structures, even the prevailing winds, is different. You may have to damage some trees by your experiments before knowing what not to do the next time. Whatever the reason is, some trees appear to be better or poorer looking than others, all with the same underlying soil make up. Then there is the nature of the underlying water drainage structure that seem to feed some trees and not the others. Some with more standing water than others after a rain, even with good drainage. With that, and its now May, I may add a cup or 2 of 10-10-10 to the poorer looking trees and lesser to the better looking trees. Some may not get any. It's an experiment. With the number of fruits I'm getting I think I can afford to lose a few and learn from it.
