Standard lemon tree types (Citrus limon) reach around 20 feet tall, with dwarf varieties growing up to 12 feet high. This tropical tree produces mildly fragrant blooms with white petalsthat have purple undersides. The lemon juice is often light yellow, but a few varieties are striped with white or green. Most lemon trees are everbearing — they make fruit throughout the year.
History
The real origin of lemon trees is lost in history, but it’s thought to be northwest India. By 200 A.D. the lemon tree made its way to southern Italy. Between 1000 and 1150 A.D., the Arabs spread this citrus tree became across the Mediterranean and European areas. Christopher Columbus carried lemon seed to the New World. Some time between 1751 and 1768, the lemon tree started to be grown in California.
Climate
Everbearing lemon trees are one of the citrus trees which require the smallest amount of heat to ripen fruit. In U.S. Department of Agriculture plant hardiness zones 9 through 11, this citrus tree thrives in cool summers and mild winters. Since the tree is constantly growing, it does not tolerate cold temperatures which occur when other kinds of trees are dormant. In the 28 to 29 degrees Fahrenheit, lemon trees drop their fruit and flowers. When temperatures drop to 22 to 24 F, the trees drop their leaves and 20 F damages the wood. Lemon trees need cold protection when winter temperatures will dip below freezing. Stringing the canopy with plugged-in holiday lights and covering with blanket usually offers enough cold protection for light freezes.
Pruning
Most everbearing lemon trees develop thorns, so wear gloves when handling the branches. In mild winter areas, you can prune the trees through the year. Light pruning involves removing twiggy growth and weak branches. More intense pruning involves shaping the tree and keeping the height cut so that the fruit is in easy reach. Lemon trees could be grown since espalier trees, but they do not create as many lemons.
Harvesting
All lemon trees are everbearing and produce fruit all year. Most of the fruit crop appears in winter and spring, while fruits occasionally develop in summer and fall. Commercially, lemons are selected when they are at the right dimensions and then treated to ripen. At home, leave the fruit on the tree until it’s ripe. New lemons are prone to bruising, so do not handle them roughly or pick them while they are wet.
