Plant Pest Series: Whitefly
Adults whiteflies are moth-like insects with powdery white wings and short antenna. Wingless nymphs (baby whiteflies) are flattened, oval and almost scale-like in appearance. Image courtesy of Planet Natural Research Center.
This month, we are featuring a series of articles that will teach you how to prevent, detect and eradicate common houseplant pests. Up this week: WHITEFLY
Prevention
Keeping your plants clean is the best way to prevent whitefly. As you do your watering routine, check your plants for abnormalities and/or bugs and remove any dead foliage. You can also wipe down the leaves of your larger plants, if you have some, with a wet paper towel. Learn more plant housekeeping tips here.
Yellow sticky traps are especially helpful in monitoring adult whitefly populations. Because whitefly spreads very quickly, it’s important to quarantine any plant(s) you suspect may have an infestation as soon as possible. This will help keep it from spreading to your other plants.
Detection
The adult flies are unsightly and annoying; the greenish larvae on the underside of leaves to suck sap and deposit sticky honeydew. Badly infested leaves turn yellow and drop. Whitefly can occur in great numbers and spread rapidly. Eradication is difficult.
Whitefly infestation on a fiddle leaf fig. Image courtesy of Epic Gardening.
Eradication
Wash them away.
Whitefly can be dislodged with a steady stream of water. Repeat the treatment as necessary. This is best for light infestations.
Use neem oil.
Neem oil is an organic oil derived from the neem tree. Use according to label instructions.
Give your plant a soapy suds down.
Make your own insecticidal soap by using a gentle dish detergent or similar soap product free of perfumes and additives that might harm plants. Mix the soap in a weak concentration with water (starting at 1 teaspoon per gallon and increasing as necessary). Spray on plants. Depending on the severity of infestation, you may need to repeat this method weekly until the infestation is completely gone. If insecticidal soap does not work after two weeks, you can try a permethrin solution.
Where possible, quarantine plants affected with whitefly outside, away from your other houseplants.