Symptoms

• Yellowed leaves throughout the canopy of your avocado tree are a sign of an iron deficiency. Malformed fruit indicates a severe deficiency.
  
  

Causes

• Improper nutrients in the soil is the number-one cause of iron deficiency in avocado trees, but alkaline soil, insufficient water or even salt spray from the ocean can lead to an iron deficiency as well.
  
  

Prevention

• Avocado roots are shallow and require frequent watering, especially in hot climates. Also make sure the pH level of your soil falls between 6.0 and 7.0, and feed your avocado twice a year with plant food formulated for citrus trees.
  
  

Treatment

• Spray your avocado with a foliar spray containing iron. Periodic soil applications of iron chelate near the roots during the growing season will reverse an iron deficiency. Spreading peat moss around your tree will enrich the soil and improve your tree's health.
  
  

Time Frame

• Depending on how severe, your avocado tree's recovery could take from months to years. Continue to treat your tree, and it will regain its health.