Gardening Help FAQs

Here are answers to some of the most common questions we receive about garden plants. You will find concise information on general gardening techniques as well as plant selection and care. For detailed information on specific plant pests and problems refer to our Common Garden Pests and Problems page.

Do you have additional gardening questions? Please contact us. Here's how.

Horticulture Questions and Answers

Which insecticides/miticides can I use on indoor plants?

Quick Reference Guide of Insecticides/Miticides for Controlling Common Pests of Indoor Plants

Chemical (a)

Type

Controls

Additional Comments

Bacillus thuringiensis israelensis

Biological

Fungus gnat larvae

Use as a soil drench to control larvae, will not control adults.

Pyrethrins

Botanical

Spider mites aphids, thrips, mealybugs, whiteflies

Contact spray with short residual. Attacks the nervous system of the pest.

Oil Sprays

Horticultural
Oils

Spider mites, scale, aphids,
mealybugs, whiteflies

Controls a wide variety of insects and insect eggs primarily by smothering and suffocating them. Excellent for scale.

Soap Products

Insecticidal
Soaps

Spider mites, scale (crawlers), aphids, mealybugs, whiteflies

Contact action. Breaks down the protective layer of the insect. Short residual.

Permethrin

Synthetic

Spider mites, scale, aphids, thrips, mealybugs, whiteflies

Contact and stomach poison. Up to four week residual

Imidacloprid

Synthetic

Aphids, mealybugs, scale, thrips, whiteflies, fungus gnat larvae

Systemic-Indoor plant products are granular formulations placed into the soil. Chemical is absorbed by the roots and translocated throughout the plant. Up to eight weeks control. Do not use on herbs!

(a) For a complete listing of common brand names of any of these chemicals in Gardening Help select the appropriate pesticide on the Pesticides page. You can also use the Gardening Help Search box or select a specific chemical from the Site Index. Some products from these pages with an indoor plant label:

    • Bacillus thuringiensis israelensis: Gardens Alive Knock Out Gnats Granules, Gnatrol
    • Pyrethrins: Earth-tone Insect Control, Schultz Houseplant & Gardens Pyrethrin Insect Spray, Ferti-lome Red Spider and Mite Spray
    • Oil Sprays: Earth-tone Horticultural Oil, Natria Multi Insect Control, Ferti-lome Oil Spray
    • Soap Products: Earth-tone Insecticidal Soap, Natria Insecticidal Soap, Schultz Houseplant Insecticidal Soap, Concern Insect Killing Soap, Safer Houseplant Insecticidal Soap
    • Permethrin: Bonide Eight Garden and Home, Hi Yield Indoor/Outdoor Broad Use Insecticide, Hi Yield Kill-A Bug II
    • Imidacloprid: Bayer Advanced 2 in 1 Insect Control + Fertilizer Plant Spikes, Bonide Systemic Houseplant Granules, Hi Yield  Systemic Insect Control Granules