Pollarding is a method of pruning that keeps a tree at a specific size. To pollard a tree, the main lateral branches are cut off very close to the main trunk. The tree then produces a callus at the end of each branch, which grows many thin branches that emanate from the callus. While pollarding has largely gone out of fashion as a method of pruning, it is sometimes practised to control the size of a tree. In Europe, lime trees, not to be confused with the tropical fruit-bearing tree of the same name, are commonly shaped by pollarding. Perform the pruning on a young tree in the early spring before the tree has leafed out or in late fall, after the tree has gone dormant.
Find the point at which you want to pollard the branches. Cut the main lateral branches off squarely at the desired distance from the main trunk. Remove any remaining side branches from the remains of the lateral branches.
Locate the top leader of the lime tree and prune it back to the main lateral branches. Remove all side branches from the trunk below the main lateral branches.
Allow the lime tree to grow for one season. The ends of the lateral branches will callus over and begin to produce thin branches during the growing season.
Prune the thin branches from the ends of each lateral branch when the season ends and the lime tree goes dormant. Avoid cutting into the callus to protect the tree from disease. Repeat this pruning practice to continue to re-pollard the tree each year.