Pruning plum trees

[JT101]

Hi all

Inherited a mini orchard in spring. Been busy, but about to tackle pruning the plum trees. I know it's a bit late. Been reading as much as I can around the subject and am fairly familiar with pruning apple trees, but not stone fruits.

These are all massive trees, and have been neglected.


I would like to know more about the growth habits of plums, especially with fruit. There really isn't much in interweb about in what wood the plums form on, how the fruit spurs form, and how to do a maintenance prune. Most sits just talk about removing dead, disease and dyeing parts, removing suckers.
But I would like to know exactly what parts of the tree the fruit forms on so I don't cut it off!!
Also seen some sites suggesting you prune back this years growth to 8 leaf buds, and any side shoots to 6 buds. Not sure how good that is, but that is the sort of thing I am looking for, Ideally in pictures and photos.

I have Czar, Victoria and RIver Early. They don't seem to have much new growth, apart from at the very top of the tree which is 20 - 30 feet in the air.

All the plums have formed only on the very ends of branches. I expected them to form on spurs running the length of the branches. Almost looks like they are tip bearers.

Will post some pictures soon

Cheers

[ameno]

Plums (and sweet cherries) do form some spurs, but most of their flowers form on the lowest 4-8 buds of the previous year's growth.
The reason yours seems to be bearing most of theirs at the tips is likely because they are mature, unpruned trees, and so do not actually grow that much year to year, and therefore last year's growth isn't much more than 4-8 buds long in the first place.

They say plums are best left unpruned except for removing dead, diseased or damaged growth, if you can. I prune mine pretty heavily, though, and they seem to do okay for it. Pruning won't really encourage extra fruit, though, unlike in apples and pears. Plum pruning is just for size control. So if the size is fine and you were just hoping for more fruit, I'd just leave them as they are, except for removing any dead, diseased or damaged branches.

If you do want to prune, that advice you found is good. It's what I do. Shorten all of this year's growth some time between July and mid-August (any earlier and they will put on quite a bit of new growth after you prune them, and any later and the risk of infection greatly increases) by around two-thirds.

[nickdub]

I'd be very wary of doing any pruning at all of a mature plum tree except for small pieces around a pencil thickness. Of course if you have a dead or broken branch the there's not much to be done except cut it right out with a saw.

Plum tree's in my experience are much more prone to catching diseases via cuts than apples or pears and I have had a couple of mature trees die on me over the years almost certainly from some infection or other. Perhaps because my garden is in the extreme West of England and quite high up, the wetter weather here makes diseases harder to dodge and my experience would be different if I lived in a drier part of the country.