Lemon trees (Citrus limon) are small to medium-sized, evergreen citrus trees. Depending upon the cultivar grown, trees average anywhere from 9 to 20 feet tall at maturity. Gardeners have choices in a wide variety of cultivars producing year-round fruits ranging in sizes of 3 to 5 inches in length. Trees start producing their yellow fruits within the first one to two years after planting. As with any fruit-bearing tree, healthy lemon trees grown in the proper conditions and given the appropriate nutrients, grow faster, better and produce more fruits more often.
Grow lemon trees outdoors in the ground in their optimal planting range of USDA planting zones 8B through 10. In cooler regions experiencing frosts and freezes, grow lemon trees in containers to protect the plant in winter. Select a cultivar appropriate for your region's growing conditions; cultivars such as Meyer lemon are tolerant to temperatures to 23 degrees Fahrenheit, but others are not so cold hardy.
Plant the lemon tree in full sun for the best growth and production of blossoms and fruit. Trees tolerate growing in partial sun, but those grown in full sun produce more fruit and grow faster.
Grow the lemon tree in a well-draining soil medium that does not hold water, for proper growth. Lemon trees planted in consistently wet soils develop root rot, slowing their growth and eventually leading to the tree's death.
Space multiple trees 25 feet apart for proper growth, blossom and fruit production. Lemon trees require adequate air circulation, and those planted too close grow poorly and produce low quantities of fruit.
Water lemon trees weekly, especially throughout the main fruiting and blossoming stage of spring through summer, or during drought conditions. Following a regular watering schedule produces healthier, faster growing trees, which produce more frequent blossoms and fruit.
Prune young lemon trees up to three years old to maintain a height of 10 to 12 feet, as this maintains good fruit production. Prune older trees--approximately 12 years old--back by one third to reinvigorate them. Keep broken, damaged or crossing branches trimmed from the tree at all times.
Fertilize lemon trees regularly to maintain their health and promote blooming and fruiting. Use a citrus blend spread underneath the lemon's canopy, broken into three equally divided applications between April and November. Apply at the rate specified on the label, and do not allow the product to touch the lemon tree's trunk.
Spray the lemon tree in springtime, after the tree has bloomed, with a citrus nutritional spray mixed with copper. Spraying the foliage with additional nutrients produces healthier, better performing trees and helps ward off diseases.