Although there are only five major groups of insect and mite pests on house plants, they are very difficult to control and highly persistent, once established. The many varieties of house plants are variously susceptible or sensitive to pests and to the pesticides that can be used for control. Furthermore, it is most difficult to eliminate all insects and mites from a plant once it becomes infested. C ontrol Measures.
Physical removal includes picking off caterpillars, slugs, and other larger pests.
Another method is to swab pests with a small brush or cotton swab moistened with rubbing alcohol. This method is feasible when plants are small and infestations very light. It is tedious and must be done once a week over a period of time. Plants can also be washed in a dilute mixture of water and true soap or insecticidal soap, or gently spray-washed with lukewarm water. Repeated washings over a period of time are necessary to gradually reduce infestations.