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WHITEFLY Back to Insect Menu



Pest Name Whitefly

Dandruff like tiny insects with two pairs of wings that are covered in a white powdery wax.

They live mostly on the under side of leaves and especially like newly unfurled leaves. Tapping the plant will cause them briefly to take flight, however once a infestation has been discovered, if possible isolate the plant as the flies will quickly spread. Foliage will eventually yellow and drop as the infestation strengthens. Like aphids, whiteflies also excrete a sticky honeydew which could attract a black sooty mold.

a) If small number of plants are affected;
Take the plant from isolation into a well ventilated area, preferably outside and spray the plant with malathion or rotenone paying particular attention the undersides of the leaves. Most sprays will not be particularly effective against the eggs of the Whitefly, so repeat the spraying every two days and when the infestation has retreated, spray every ten days to insure all Whiteflies in different stages of growth are destroyed. For minor infestations, wipe the underside of the leaves with an alcohol soaked cloth and then rinse with a strong spray of tepid water. Always wash your hands after handling an infested plant to prevent the spreading of their eggs to other plants. An insecticidal soap spray can also be used.

b) If large number of plants is affected:

OPTION 1:Non Chemical management:

  • Do not overfertilize. Whitefly numbers increase with increasing foliar nitrogen levels. If necessary, switch to a slow-release fertilizer and/or one with less nitrogen.
  • Lightly vacuum plants in the early morning to remove cold, slow-moving whiteflies
OPTION 2: Chemical management:
Several applications may be necessary about 5 to 7 days apart. Apply when first noticed.
  • Lilly Miller Diazinon Insect Spray
  • Lilly Miller Feed & Shield Systemic Rose Care 6-10-4
  • Ortho RosePride Systemic Rose & Flower Care
  • Safer Insecticidal Soap Concentrate
  • This list may not include all products registered for this use.
Active ingredient table for the above listed products:
Product Active Ingredient EPA
Lilly Miller Diazinon Insect Spray diazinon 802-444
Lilly Miller Feed & Shield Systemic Rose Care 6-10-4 disulfoton 802-426
Ortho RosePride Systemic Rose & Flower Care disulfoton 239-2134
Safer Insecticidal Soap Concentrate potassium salts of fatty acids 42697-1