Mature citrus trees require little pruning. Young, vigorous trees may require some pruning. Basically, prune only as needed. Otherwise, don’t prune. The best time to prune a citrus tree is mid to late March. Do not prune after September to reduce encouraging late growth. Young, tender growth produced late in the season is more susceptible to cold injury.
As the tree matures and slows down in growth, it will be less likely to produce as many long vigorous shoots. A common mistake, which results in the tree producing an abundance of these vigorous shoots, is to fertilize too much. The tree’s caretaker may not realize he or she is overdoing it by not considering the extra fertilizer the tree is getting from surrounding or nearby lawn areas.
Tree roots extend well beyond the tree’s branch spread, growing into adjacent lawn areas. A tree’s root system extends two to three times beyond the tree’s branches. In most home landscapes, there is lawn grass in close proximity to a citrus tree. As you fertilize your lawn, a nearby tree will have access to the lawn fertilizer. In addition to this fertilizer, many people also fertilize their citrus tree. As a result, the tree gets too much fertilizer and may produce an abundance of long fast growing shoots.
Fertilizing correctly should lessen the need to prune overly vigorous vegetative shoots. Also, an overly vigorous tree typically produces less fruit. Its energy is used to produce leaf and shoot growth instead of fruit. Some commercial growers remove fruit from young trees during the first few years to encourage strong vegetative growth. Don’t get discouraged as the quality of fruit produced on a young tree is usually poor compared to the same tree when mature.
During the first few years (on young trees), apply frequent, light applications of a citrus fertilizer approximately every six weeks, March through mid-May. Avoid fertilization during the summer rainy season because of potential leaching of the fertilizer. Do not fertilize between October and the middle of February to prevent winter growth flushes.
Apply fertilizer uniformly in a three foot diameter circle around the tree. As the tree becomes older, the area fertilized should be enlarged as the root system expands. Never apply fertilizer in piles or mound fertilizer against the trunk.
Mature trees may be fertilized a maximum of three times per year, spring, early summer and again in late summer. But your tree may produce more fruit when fertilized only once or twice per year. Base this on experience, soil type and tree response.
You’re better off under doing it versus over doing it in fertilizing and pruning citrus.
Larry Williams, UF/IFAS Extension Agent, Okaloosa County, March 1, 2017