Question: My aglaonemas have white insects on the backs of their leaves. The plants appear to be dying. What will kill them?

Answer: Those are mealy bugs, and you can use a general-purpose houseplant insecticide, or you can clean most of them off with a cotton swab or cotton ball dipped either in the insecticide or in rubbing alcohol. (Wear disposable rubber gloves.) They are quite prolific, and they can spread to many other types of plants. You really do need to eliminate them.