How to Spray Olive Trees for an Olive Knot
- 1). Dissolve 1 lb. of copper sulfate into 1 gallon of warm water in a plastic bucket. This can be stored in a glass container, sealed with a stopper, indefinitely.
- 2). Mix 1 lb. fresh hydrated lime with 1 gallon of water. Let the solution stand for two hours.
- 3). Label both mixtures and store them in a safe location until they are ready for use. They are toxic and corrosive.
- 4). Combine the lime and copper sulfate right before spraying. Pour 2 gallons of water into a plastic bucket. Shake the copper sulfate and pour 1 qt. into the bucket. Agitate the lime and pour 1 qt. of that into the bucket. Stir the mixture continuously while combining the ingredients and for a few minutes afterward. This makes 2 1/2 gallons of a 10-10-100 Bordeaux solution.
- 5). Pour the mixture into a sprayer. It is now ready to use. Shake the sprayer as you use it to keep the mixture from clogging the instrument. Aim the solution at the olive trees, focusing on the young branches and twigs that are prone to olive knot.
- 6). Spray olive trees at least twice -- after the harvest of olives and again in the spring when the leaves drop, from March through May, because the scars are prone to infection. This will help control the disease. Use a slightly stronger mixture, as described above, mixing 1 1/2 qt. of each solution with 2 gallons of water or use a fixed copper spray.
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