Why is the bottom of the trunk black? Water? Maybe you are overwatering it and it is drowning, and that's why the buds are dropping.

Carla in Sac

It usually takes some time before persimmons fruit after you plant them. My experience is that the fruits on the plant when you buy it always drop. Next year you probably will get 2-3 fruits and in two years, if persimmon is comfortable at your place, you will have first real crop.
Olga

The trunk isn't black...it's just cuz I took the picture after I watered.

So the persimmon won't grow fruit if it remains in the pot? It's going to be several months before I can plant it, maybe I shouldn't have bought it so soon :( I bought it because it had so many buds and i thought each of them would turn to a fruit, instead they're all falling off...

You can replant it in a bigger pot to wait several months until it can get into ground.
Olga

Well, no, that's not true, all my trees are in pots including the persimmons, and 2 of my 3 persimmons fruited the first year after I planted them.

Since you only took a picture of the pot and not the branches, it's hard to say, but the tree is probably too small to carry 30 fruit. And the pot in the photo is very small, my trees are in 1/2 wine barrels.

So it could be dropping fruit because it is stressed from heat or cold or small pot size, or because it is trying to keep the right amount of fruit for its size, or because you are overwatering it.

But don't be too unhappy, your tree is better off because persimmons will over-set fruit. Mine did and it snapped at the base because I hadn't thinned and left too many fruit on it, it got too heavy, and instead of dropping fruit, the tree trunk just split.

Carla in Sac

persimmons are persnicky. once i got a couple on the second leaf, but 4 years seems to be what they like before producing. & they're famous for dropping fruit until they're older.

my persimmon tree had two buds last year and they both dropped. I was told by my nursery that the tree was testing to see if it was mature enough to fruit and would likely be ready this year. So far so good this year, as I have over 100 buds that are flowering and starting to develop fruit. Hopefully that stays the case through October. My tree is 7 ft