Question
I'm in Southern California and have a neglected (no fertilizer or water for years) Avocado tree that I just had trimmed.  What is the best type of fertilizer (if needed) to use, and how often.  This tree hasn't borne fruit for at least 20 years and I'm trying to revive its production.  Any other tips?  Thanks.

Answer
Nitrogen and potassium are necessary to produce large high quality fruit. A 10-5-20 fertilizer is generally used after trees begin to bear fruit to provide the needed nitrogen and potassium. 3 or 4 applications per year at a rate of 4-5 lbs per tree but, not to exceed 20 lbs per tree per year. Spread around the tree and water into the ground. Check with your local nursery/garden type store and they should have this fertilizer.