Answer: Most fruit trees are pruned in the winter when they are dormant and it is easier to see the branch pattern. You can prune yours now if the tree is small and you can see the branch structure. The goal is to obtain an open center and to remove any crossing, rubbing or broken branches, plus anything that is pencil sized or smaller. You can head back the larger branches to promote a more compact growth habit and fruiting spurs. Your local cooperative extension office will have publications on pruning fruit trees or you can see diagrams of fruit tree pruning steps in the book called Pruning by Christopher Brickell. Your library probably has a copy. Some plum trees need a second tree for good pollination and fruit set so find out the name of your tree and do some research on whether or not it is self fruitful. If it is not setting fruit, it may need a companion plum tree. Best wishes with your tree.
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