Lemon trees are evergreen plants, meaning they retain their foliage year-round rather than dropping their leaves in the fall. These trees are desirable not only for their fruit, but also for their pleasing appearance. Some types of lemon trees have dwarf varieties that are often grown in containers as ornamental plants. Lemon trees are relatively easy to care for as long as you protect them from freezing temperatures, according to Texas A&M University.
Lemon trees are warmth-loving plants. They are very sensitive to cold, according to the Tree Help website, and should only be grown in areas where temperatures do not drop below freezing. This is usually defined as tropical and subtropical areas, or U.S. Department of Agriculture (USDA) growing zones 10 and 11. Lemon trees must be protected during periods of hard frosts, especially in late spring when they are blooming. For that reason, they are often grown in containers, where they can be brought indoors when cold weather threatens.
Grow lemon trees on the east side of the house, where the morning sunlight can quickly warm up the tree. They can suffer from windburn, so placing them where they are protected from cold, drying winds is important. On the other hand, lemon trees should not be crowded together, according to Purdue University. Trees that are spaced less than 25 feet apart may show reduced fruit production.
Lemon trees are highly adaptable to all different types of soil conditions, as long as the soil is well-draining. Too much water in the soil can cause the roots of the citrus trees to rot. Heavy clay soils sometimes retain too much water and can slow the growth of the tree, according to Purdue University. Sandy soils, however, are popular for growing lemon trees, especially in Florida.
Lemon trees thrive when they receive a full day's worth of sunlight. Herbicides should not be used around them, as they are quite sensitive to the chemicals, according to Purdue University. Instead, control for weeds by manually removing them. Encourage a bushier shape and more prolific lemon production by pruning to keep the height of the tree around 10 to 12 feet at the tallest. Water every seven to 10 days or enough so that the soil remains slightly moist, but never waterlogged or soggy. Do not mulch citrus trees, including lemon trees, but build a soil bank around the tree in early fall to protect it from cold temperatures. Remove the soil in the spring, when all danger of frost is past.
Mites and scale both attack lemon trees, but can be controlled with insecticides, as lemon trees are not as sensitive to insecticides as they are to herbicides. Diseases are a more serious problem, according to Purdue University. Many fungal diseases can attack all parts of lemon trees, causing everything from harmless but unattractive leaf spots to serious rotting of the fruit. Prevent fungal diseases by treating your lemon tree with a copper-based fungicide in the spring. Follow the directions for application on the label according to the size and age of your lemon tree.