Angelina from Seattle, Wa writes
Bonide Liquid Copper Fungicide is not labeled for use on olive trees. Unfortunately, we do not currently sell any products labeled for Olive Peacock Spot/leaf spot. Olive trees can be sensitive to Neem Oil, which is what is commonly used on edibles for disease, so we are not sure this would be a safe application. We suggest contact a local Master Gardner for recommendations on how to treat this disease.
Answer last updated on: 01/02/2017