Lemon trees not only provide shade and a delicious harvest of fruit, but they also add aesthetic appeal to your landscape. This citrus thrives best in warm environments, but can be grown in cooler climates. Some key things to keep in mind when caring for a lemon tree is to protect it from cold temperatures, provide extra nutrients and protect the tree from disease.
Provide Extra Nutrients
Lemon trees, like all trees, benefit from extra nutrients added to their soil. Lemon trees not only need the basic nutrients of phosphorus, potassium and nitrogen, but also benefit from micronutrients like magnesium and zinc. Add these to your lemon tree with a slow-release fertilizer applied in fall and in spring. For lemon trees with yellowing leaves, an iron supplement is needed.
Protect from the Cold
Lemon trees are the least cold resistant in all of the citrus family, and exposure to cold conditions will prevent the lemon tree from absorbing nutrients, damage the fruit and harm the bark. It is important to protect your lemon tree from cold temperatures before it arrives. First, remove the mulch from around the base of the tree, as mulch usually keeps out sunlight and retains cooler moisture. Young lemon trees will be protected if you pack up the soil to two feet higher around the trunk or use a tree wrap for insulation.
With more mature trees, use a blanket that is large enough to cover the branches. You can even light a small fire close to the tree to warm it up, but make sure it is away from anything that could catch fire, such as branches, twigs, the trunk or leaves. Keep in mind that if it is too cold for too long, there is little you can do to protect your tree.
Insects seem to like citrus trees just as much as humans, so it is important to protect lemon trees from the damage they create. This damage could prevent the tree from providing fruit or even halt growth. If your lemons have any sort of scabs, your tree has citrus canker, a bacterial infection. Prevent this disease as best you can with a copper fungicide spray in early summer.