Things You'll Need
Snub nose loppers
The sub-tropical and evergreen nature of citrus trees combined with the warm to temperate climate of Southern California means citrus trees can grow nearly year-round. Virtually all major species of citrus do well in the frost-free or low-frost areas of Southern California, according to the University of California Davis Extension. As a rule, citrus trees require very little pruning for fruiting performance. They can tolerate some light pruning to remove problem wood or to control the size and shape of the tree canopy.
Prune your Southern California growing citrus trees during the winter, from December to January, when they are in their slowest growth phase.
Trim away dead or diseased twigs, branches or limbs, or any that look as though they may be badly infested with insects. Collect the problem cuttings from the soil and canopy. Dispose of them, bypassing the compost bin to prevent potentially spreading disease.
Sever any suckers or water sprouts that crop up around the base of the tree or appear growing vertically within the canopy.
Thin the number of branches. Cut back the tips of lemon tree branches to control overgrown, disproportionate shoots and make access to the fruit easier. Remove several of the oldest, lowest producing branches every few years. Reduce the length of the longest branches by up to one-third, as needed.
Refrain from trimming or pruning grapefruit trees up to 20 years of age other than to remove deadwood, as the raw wood cuts can be an invitation to Rio Grande gummosis disease.