why are plums falling off before they are ripe?

[cc-rider]

I've had this plum tree for nearly 10 years now, and it's HUGE! It gets loads and loads of plums on it, but they ALL fall off before they get plump and ripe. They start to turn purple, and then they fall off the tree....hard, purple little plums.

It's probably the only plum tree around...is that the problem? Pollination?

It's frustrating! I noticed that the apple tree is doing the same thing this year.

I'm in zone 5 if that makes a difference.
CC

[CSA again]

Could be theres just too many for the tree to handle

its just thinning itself out, could make the ones remaining larger and better

I've seen my tree do that before when it had way to many plums on it

[Cliff]

google plum curlico
I'd think that would be the most likely culprit.

[haypoint]

It is natural for fruit trees to thin out the fruit. About now, the cluster of apple blossoms has turned to a group of tiny apples. Most of those will fall off, leaving only two or three apples. If you want better sized apples, you hand thin them down to a single apple on each cluster.
But that is a bit off topic.
Your plum tree is thinning itself. If it is dry, it will shed more fruit. It takes a lot of energy for a tree to produce fruit. If it isn't getting pollenated, it will not produce any tiny plums at all.

[Alice In TX/MO]

Are you fertilizing, too?

[where I want to]

Could be lots of stuff. Without looking personally, just throwing out stuff...........
1) Could be the tree was grafted and the grafted part dies, leaving a non-productive sprout from the root.
2) Most plums seem to be self-fruitful but maybe you're right about needing a pollenator. You could graft another variety that blooms at the same time onto the existing tree- easy to do.
3) if the tree is stressed (lack of water or too much, too little light,etc) it will shed fruit rather than mature it.

[ldc]

I'm guessing (if this has never happened before) that this is a rain and temperature problem. This has been a spring of extremes in most parts of the country, so what about where you are? Too much rain, then none? Too cold, then rapidly rising temps? Might be an off year...best wishes, ldc

[Cliff]

Plum curlicos cause this. Do the fruit have tiny crescent shaped cuts in them?
They get to the fruit at bud-break and lay their eggs inside. The affected fruit drop just before ripening. The wormies eat and mature then pupate just under the surface of the soil and in leaf litter till next spring.
We had them bad this year. As of now our chickens are having a good ole time in the orchard digging for bugs.

[Beltane]

Yes, what Cliff said. We've had good luck using Surround, but you really have to time the applications right. It consists of very small particles of kanolin clay that are sprayed onto the developing fruit starting at pink or petal fall. The clay makes a barrier against the buggers. Check the fruit that has fallen...do any of them have the crescent moon cut out of them? Then you'll know for sure. Good Luck.

[Rocky Fields]

Hey.

Trees need plenty of water when growing fruit.

RF