Answer: Left unchecked, an aphid population can kill a plant. Your treatment of plain water was a good one, but one that has to be repeated once - even several times a day. To kill the aphids, try using an Insecticidal Soap. It's made of fatty acids from certain plants and is effective against soft-bodied insects like aphids. Aphids are especially difficult to control because they bear live young that are capable of bearing live young almost immediately. Therefore, you can have three or more generations feeding on the same leaf and stem at the same time! You can use Insecticial Soaps every 7-10 days for control. Read and follow label directions, especially the time period you need to wait after spraying before harvesting your peppers.
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