How to eliminate whiteflies?
How to eliminate whiteflies?
Whiteflies fly and reproduce quickly; eliminating them requires patience and sustained effort.
Timing of spraying
- Morning or evening — whiteflies are less active at lower temperatures, making these the best times to spray.
- Avoid spraying at midday when temperatures are high and whiteflies are active and will fly away.
- Choose windless days for spraying.
Application method
- Leaf undersides are the main target — adults, nymphs, and eggs are all on the undersides.
- Lift leaves and spray from below upward.
- Spray until the undersides are dripping, ensuring full coverage.
- Also spray the soil surface and surrounding countertops to kill fallen insects.
Why multiple sprays are needed
Whiteflies have severe overlapping generations — eggs, nymphs, pupae, and adults coexist on the same plant:
- Sprays containing dinotefuran are effective against adults and nymphs.
- But they are less effective against eggs.
- Therefore, one spray cannot kill all life stages; reapply at 5-7 day intervals.
- About 3 consecutive sprays are needed to cover the entire life cycle.
- Leaf undersides must be sprayed until dripping.
Integrated control
- Yellow sticky traps — whiteflies are strongly attracted to yellow; place traps 10-20 cm above plants for mass trapping.
- Remove old leaves — pick off heavily damaged older leaves to reduce population density.
- Isolate — immediately isolate plants with whiteflies.
- Remove leaves before spraying — old, heavily damaged leaves have the most eggs; remove them before spraying for better results.