Lime trees are easily recognizable citrus trees. They produce limes, a citrus second only to lemons in flavoring foods and drinks. As subtropical trees, they cannot grow in many areas of the United States. Most homeowners, however, try growing them on a small scale as potted plants.
Lime trees come in many different varieties that vary in height and width as well as fruit shape. The most popular variety is the Mexican lime, which produces a short, bushy tree up to 13 feet tall with oval or round fruits that rarely reach 2 inches in length. Tahiti lime trees grow up to 20 feet tall and produce 2 3/4-inch fruits. Other varieties include the giant key lime, the rangpur lime, the Palestine sweet lime and limequats, which are hybrids between Mexican limes and kumquats.
Lime trees cannot withstand any frosts and need protection when the temperature drops. Planting them on the south or southeast side of a building will help provide this protection. The tree prefers full sun and well-drained soil. Clay soils, with high water retention, will cause problems including root rot and lower fruit production.
Lime trees require deep watering when planted so they can establish themselves. They need ammonium sulfate fertilizer after they start growing to encourage foliage production. Drape a blanket or tarp over the tree in winter for extra protection against frost and cold.
Mexican lime trees grow faithfully from seed, but most other types need T-bud grafting in order to produce hardy, disease-resistant plants. You may also propagate lime trees with air layering, but these trees usually are susceptible to root rot.
Few pests and diseases become life-threatening to the lime tree, but control of these common diseases will help keep the tree healthy. Root rot kills the tree slowly. Aphids, spider mites, scale and Asian citrus leafminer will eat at the plant, but will not usually kill it. Citrus canker, oil spotting and anthracnose also detract from the aesthetic appeal of the limes, but will not kill the tree.