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How to prune citrus trees
Prune at least once a year.
Once a citrus tree is established and producing fruit, it needs to be fully pruned every 12 months. Go ahead and mark your pruning dates on your calendar, so that you don't forget them.
If your tree suffers from disease or damage, add another pruning session in. If you've pruned a tree down to its base before, it may take a few years for it to recover fully enough to benefit from an annual pruning.