The olive tree needs careful pruning every other year when it produces flowers and then olives.
Why Prune an Olive Tree
Olive tree care involves pruning for several reasons: first, to reduce the weight of the olive fruit on the limbs. Second, prune to allow more light into the center of the tree's canopy so olives there can ripen. Third, prune to reshape the tree so branches grow outward. Harvesting lateral branches is easier than picking from treetops.
When to Prune an Olive Tree
Prune an olive tree when it is 4 years old and in the spring after winter rains, to prevent water-borne infections. Prune while the tree is flowering, so you can tell where the fruit production will be either overabundant or sparse.
When Not to Prune an Olive Tree
Do not prune olive trees during the "off" years if at all possible.
How to Prune an Olive Tree
Cut from the top ("topping") to reduce height. Make topping cuts far from branch junctions. New growth will shoot upward from these cuts. Cut away excess branches in the canopy to allow more light so the olives can mature. Thinning cuts are done close to a bud or branch junction.