|Whiteflies have taken over my hobby greenhouse. How do I get rid of them without killing the plants?
|Whiteflies are effectively controlled by several products which are natural or organic. Some options are products containing Neem, insecticidal soap, or one of the lightweight summer oils. Always read the label before purchasing the product to make sure it is labeled for the plants you will be spraying it on and for greenhouse applications.
It is important to direct sprays upward from beneath the plant for effective control. Be ready to repeat sprays once or twice at 10 day to two week intervals, as new eggs will hatch and pupae will continue to emerge for a while. If you look carefully under the leaves you will see small yellow/green scale-like things (the size of a typed "o"). These are the pupal stages of the insects and will soon emerge as adults. Spray early in the morning when temperatures are cool to avoid burning the plant.
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