Kitchen Garden Forum

On the "Coe's Golden Drop" plum tree, which ripens late, some plums are rotten but unripe. Those not showing as rotten are still rock hard.
The tree is about 15 years old.

Not much of a tree fruit expert but something has obviously happened to some of them.
Wonder if its worth picking some of the hard unripe fruit early so that perhaps they have a chance to ripen off the tree away from whatever is causing the infection?

Dear Stephen,
looks like a classic case of brown rot to me. You need to pick off as many of the affected plums as possible and bin them - DO NOT compost them. The spores may survive the heap and go on to infect other things in your garden. This rot will affect the fruit of most trees so make sure you keep things clean. Some may fall off but most of these affected fruits will continue to hang on to the tree over winter as shrivelled 'mummies'. When you get the ladders out to do your winter prune all these shrivelled fruit should be removed as well as any remaining fruit on the ground. If they are left they will reinfect your trees next summer and the problem will get worse. It is best if you can get the rotting fruit off the trees before the pustules on the outside form as they are the spore bodies that will infect the rest of the crop.
Regards Sally Wright.

Hi Sally
Your expertise is very welcome. It's like having our own personal GQT!
Thank you. I will follow your advice (it involves a bit of going through the compost heap).
Stephen

I would also advise to treat the tree (and preferably those trees that are nearby) with a fungicide. Search the internet for a suitable option or ask at a farm store.

It's some disease

Brown rot again this year.
Is the optimum approach to remove the trees and put something else it their place?

I wonder if you have any fruit orchards nearby who might be faced with this problem on a regular basis?
If so, talking to the owners and discovering how they deal with this problem might provide some insights.

Hi Stephen,

I got Brown rot on Plum Beauty & not a fruit, & just as a slap in the face the Victoria had the worst case of downy mildew & I'm limping along just 4 plums on it - watch the wasp's find them! I've been asking around at the plot & I think I have to be brutal & cut them back more severely to let more air circulation & suffer another year of no/few fruit. I think they may be right as both trees have grown way bigger than the root stock indicated. That means every few years I could be without a crop but first year that they haven't provided so hoping I might be able to nip it in the bud - so to speak!

Thank you both.

No local orchards, I'm afraid.

More air? I understand this might be an issue. Certainly the trees are bigger than I want. The garden is enclosed.

I'll post a picture or two later.