Hi Mark –
Whitefly are often found in thick crowds on the undersides of hibiscus leaves. When infested plants are disturbed, great clouds of the winged adults may fly into the air. Both nymphs and adults will damage these plants by sucking the juices from new growth causing stunted growth, leaf yellowing and reduced yields.
Here’s how to get rid of these small sucking insects using proven, organic techniques.
Yellow sticky traps are helpful for monitoring and suppressing adult populations.
If found, use the Bug Blaster to hose off plants with a strong stream of water and reduce pest numbers.
Natural predators of this pest include ladybugs and lacewing larvae, which feed on their eggs and the whitefly parasite which destroys nymphs and pupae. For best results, make releases when pest levels are low to medium.
If populations are high, use a least-toxic, short-lived organic pesticide to establish control, then release predatory insects to maintain control.
Safer® Soap will work fast on heavy infestations. A short-lived natural pesticide, it works by damaging the outer layer of soft-bodied insect pests, causing dehydration and death within hours. Apply 2.5 oz/ gallon of water when insects are present, repeat every 7-10 day as needed.
Organic Neem Oil can be sprayed on vegetables, fruit trees and flowers to kill eggs, larvae and adults. Mix 1 oz/ gallon of water and spray all leaf surfaces (including the undersides of leaves) until completely wet.
Fast-acting botanical insecticides should be used as a last resort. Derived from plants which have insecticidal properties, these natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
Tip: Horticultural oils, which work by smothering insects, are very effective on all stages of this pest, but may damage blossoms if applied to heavily.
Hope it helps!