Insecticide for Houseplants

Use only safe, approved insecticides on your houseplants.Jill Fromer/Photodisc/Getty Images

Houseplants bring a touch of life and greenery into your living environment. Because they live within the same walls you do, houseplants also share the air you breathe, and you and other family members are likely to come into physical contact with your houseplants each day. To control bugs, choose a safe insecticide for your houseplants that won't create health hazards in your home and for your family.

Rubbing Alcohol

Common rubbing alcohol applied to plant leaves with a cotton ball can help remove aphids and mites, while alcohol remaining on the leaves also has an insecticidal effect on remaining bugs, according to Lee Townsend, extension entomologist at the University of Kentucky College of Agriculture. You also can spray alcohol on the leaves with a mister, says the Colorado State University Extension website, but test a small part of the plant first, as alcohol can cause leaf burn in some houseplant varieties.

Insecticidal soaps are the most common household insecticide, reports the Colorado State University Extension website. Liquid hand and dishwashing soaps may also have insecticidal properties, but they can damage your houseplants due to additional ingredients within them, such as degreasers, skin softeners or artificial scents. Insecticidal soaps sold at your local garden center are specifically designed to avoid doing damage to your houseplants. Don't hold the pump sprayer too close to your houseplants, warns Townsend, as the concentrated spray can damage plant leaves.

Several brands of pyrethrin insectides are approved for indoor use. Pyrethrin is a natural substance extracted from chrysanthemums. Natural pyrethrin insecticides have the advantage of being fast-acting with low toxicity, according to the Colorado State University Extension website. Natural pyrethrins also have a short persistence time; they dissipate from your plant's leaves within a few hours. Some synthetic pyrethroids have higher toxicity and remain active on your plants for several days, making them more of a concern if you have pets or small children who might touch or chew on the houseplant's leaves.

Bacillus thuringiensis, commonly known as Bt, is a natural soil bacteria with a proven ability to control insects. Different strains of Bt have been developed to combat specific plant pests. The israelensis strain is particularly effective on gnats, blackflies and mosquitoes, including the control of fungal gnat larvae on houseplants, according to the Colorado State University Extension website. Bt is non-toxic to humans and pets.