The Mexican lime is the most widely cultivated acid fruit in world trade today. You may know the fruit as the West Indian or Key lime. The Mexican lime tree is shrubby and vigorous, growing between 6 to 13 feet tall. The branches are thorny and the leaves have a fresh citrus scent that can fill any room. The fruit from these trees are small, reaching only 1 to 2 inches in diameter at maturity, and the color is light green to yellow. Mexican lime trees do not tolerate frost but can be grown in containers and wintered indoors.
Water the young trees by creating a soil ring or basin encompassing the entire diameter of the root system. The ring should hold 8 to 10 gallons of water and filled twice a week for the first month and once a week from then on throughout the first growing season. The soil ring will eventually wash away and at that point the tree is said to be established.
Apply a citrus tree fertilizer three weeks after planting and every 6 weeks after through October. Do not allow the fertilizer to contact the trunk of the tree and follow manufacturer's directions on the amount to use depending on the age and size of the tree.
Spray the foliage once a year in the spring with a manganese and zinc foliar spray. This will keep the tree from developing a micro-nutrient deficiency.
Spread a 2-inch layer of compost over the soil above the root system of the tree. Regular watering will leach the compost into the soil keeping it loose and well-draining. The compost will also add nutrients to the soil.
Pull weeds from under the drip line of the tree. Young trees cannot compete for moisture and nutrition and weeds or lawn grass against the trunk of the tree can promote fungus diseases. Mulch should not be used around citrus trees; however a weed mat from the local garden store will keep the area weed-free. Whatever you use to keep the weeds from growing, keep it a few inches away from the trunk of the tree.
Prune off all suckers from the base of young trees. Cut off dead or damaged branches as soon as you notice them and make all cuts flush against the trunk of the tree. Mexican lime trees do not require pruning to shape or train the trees.