Lemon trees provide a splash of bright color, a pleasant fragrance, moderate shade, and a delicious bounty of fruit to any garden. It is easiest to grow this citrus tree in warmer environments, but it is possible to grow them in cooler climates as well. When growing a lemon tree in any climate, you tree will be healthier and produce more fruit when you fulfill its special care requirements.
Protect From Cold Temperatures
Since lemon trees are the least tolerant to cold temperatures of all of the citrus family, according to Texas A&M University Extension, they need adequate protection if you want to grow them in places with any sort a drop in temperature. Exposure to cold will cause the lemon tree to shut down, drop fruit and make it more susceptible to disease or insect infestation. The best way to prevent this is to anticipate cold temperatures, and to take action before it arrives.
Remove any mulching from around the lemon tree, since this blocks out sunlight that will warm the soil around it. Protect young lemon trees by piling up the soil about two feet high around the trunk--called "banking" according to Texas A&M--or you can even use a tree wrap (available at gardening stores) for added insulation. To protect mature trees, cover the entire top of the tree with a blanket that will reach around the branches and hang towards the bottom of the trunk. Keep in mind that if it is too cold for too long, there is little you can do to protect your tree.
Provide More Nutrients
All trees, especially fruit trees, benefit from fertilization. Lemon trees are no different. Not only does this citrus need the basic elements of nitrogen, phosphorus and potassium, but also zinc and magnesium micronutrients. Provide these nutrients for your lemon tree each spring and fall season with a slow-release fertilizer. Add an iron supplement if you notice yellowing leaves on the tree.
Since citrus trees can catch disease easily, it is important to provide protection as much as you can. Insect and disease damage can prevent the tree from fruiting or even maturing. Observe your lemon harvest. If they seem to have any sort or sores or scabs, TreeHelp.com advises that this mean your lemon tree has citrus canker, a common bacterial infection. Prevent this disease as best you can with a copper fungicide spray in early summer, since the disease symptoms pop up in late summer to fall.