Avocados are among the most tasty and nutritious fruits around. Used as a vegetable, this member of the Laurel family can become a 25- to 60-foot-tall tree that provides lovely shade, adds to the beauty of your landscape and produces abundant fruit when you give it the conditions it needs. Avocados came to the United States from Central and South America and are primarily tropical plants. Most varieties of avocados are frost tender, but they will grow fairly large in USDA climate zones 8 through 11. Unless you purchase a grafted avocado tree, you should not expect it to produce fruit.
Caring for an Avocado Tree
Plant your young avocado tree in an area with well-drained soil that receives full sun and is protected from heavy wind and frost. Dig your hole the same depth as the tree's root ball and a little wider. Place the tree into the hole gently and do not disturb the roots any more than you must. Refill the hole with the soil you dug out. Water it well.
Allow the soil to dry out before you water your tree again and be sure not to over water it throughout its life. But do soak the roots well when you water.
Lay a thick layer of coarse mulch, such as redwood bark, under your tree. Do not allow it to touch the trunk. This mulch can help to prevent root rot and can deny certain insects the habitat they need.
Apply a balanced fertilizer in small quantities four times each year. Avocados need a little nitrogen, phosphorus and potassium in balanced amounts, along with a small amount of zinc. Your young tree needs 1 to 2 tsp. of a liquid fertilizer each year, which you can apply in three or four applications.
Prune your avocado in fall or winter when it grows larger if you want to control its shape and size. Avoid pruning in hot weather because the tree can become sunburned.
Control insect pests, such as the avocado thrips, if they occur. Using mulch can help to deter this insect as can pruning the tree in January. If the thrips problem becomes severe, you can spray with the Entrust formulation of spinosad, which is organic. Snails can attack young trees. If they do, spread diatomaceous earth or iron phosphate granules around the tree.