Trouble with Avocados

Question from Monty:

I live in Irvine, CA. I have several citrus and stone fruit trees espaliered in my back yard and doing fine. However, I have two avocado trees that continue to struggle (four and six years old). They get good sun, but not all day sun. There are large palm trees on either side. I get new growth each year, but neither tree is getting larger and I never get fruit large enough to eat. I have tried different watering schedules, am careful not to clean up under either tree, and try to feed both trees on prescribed schedules. I am wondering if I’ve planted these avocado trees in a bad place. Do you think the palm roots are over powering any efforts I make to help the avocado trees? Is there something else you can suggest I could try?

Answer from Pat:

Avocado trees need full sun and adequate space in which to grow. When growing in shade and competing with roots of other old established trees avocado trees cannot not do well. In order to compensate one must apply more fertilizer than otherwise necessary and make sure that the trees are also well watered. You have to figure that other plants are stealing not only the sunshine but also some of the fertilizer and water.

Feed your avocado trees now in February divide the total amount into four applications and spread the feedings out to mid-summer. A mature avocado tree needs as much as 2 pounds of actual nitrogen per year as well as adequate amounts of other nutrients such as phosphorus, potassium and trace minerals especially zinc. Follow the instructions in the February chapter of my book. Don’t skimp on nitrogen. Blood meal is a strong organic source of nitrogen.

I have a neighbor who planted two avocado trees in a semi-shaded place near large cypress trees and it is always cool there from ocean wind. These avocado’s have not grown one inch since he planted them. They are also afflicted by gophers. If those trees were mine, I would trap the gophers, up the feeding and increase irrigation. I should caution you, however, that young, non-bearing avocado trees can be damaged by overfeeding so I wouldn’t be carried away by too much enthusiasm. Wise and appropriate feeding is what is necessary and watering it in to make sure the fertilizer is reaching the roots. I don’t think my neighbor was very wise to have planted avocado trees in such a bad location.