I would not suggest spraying for just a few catepillars. If you get a lot more try using a product containing B.t. which is a natural caterpillar killer. Feed the papaya with a lawn type fertilizer with a ratio of nutrients of 3-1-2 or 4-1-2 or similar. Apply 1-2 cups per 50 square feet of soil surface area and water it in well.
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