Pruning an orange tree stimulates growth and improves the overall health of the plant. When pruning, look for green shoots, dead or damaged branches, limbs that hang too low to the ground, and branches that rub or damage the fruit.
Any large amount of pruning should be done after last frost as to not to leave the tree exposed. Always use sharp, sterile shears or saws when pruning to protect the tree from disease. Citrus trees are also susceptible to sunburn. If pruning exposes new sections of the tree to sunlight, those sections should be covered with a white latex or whitewash tree paint.