As far as I know, Plum Trees should be pruned in early Spring, before the trees bud out. So that is what I usually do. However, I am wondering about the suckers that grow quite aggressively from the bottom of the tree. Can those suckers be cut off any time of the year? Or should I wait until next Spring and do it as part of the regular pruning cycle? I like to do whatever is best for the tree. - - - Changing gears somewhat, some of you may have read about my attempts to graft plums. I am happy to report that I've had mixed success. Two of the grafts worked, three did not. (But that's better than last year: 0 success.) I don't know what the rootstock is, but I asked around some of my Italian friends (who all seem to have Plum trees) and got a few whips from their yearly pruning activities. So I now have a couple branches of Italian Plums that are supposed to be delicious. I'll put the word out again next Spring, to get some more whips, hopefully different varieties. I've seen a few young trees at the nurseries that have five types of Plum already grafted onto them, for gardeners with not much room, but it's a lot more fun to try this myself.
Suckers can be pruned at any time of the year. I prune all of my fruit trees whenever I see any undesirable growth. That means removing most new growth whenever time is available, since many of the trees are as large as I want them to be.
If you are out by the tree regularly, you can prevent the suckers from forming by rubbing the buds off with your gloved hands before the buds leaf out. Quick and easy. Neighbours may look askance at you for stroking your trees though.
