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How to identify it
- Adults are about 1/16 inch (1.5 mm) long and look like tiny white moths. Under the powdery white wax the body is light yellow, and the eyes are dark brown.[1][3][2]
- Crawlers are minute and yellowish and look like grains of pollen moving on the leaf.[1][2]
- Older nymphs are oval and scale-like, light yellow to orange, with no wax on them. The pupal case, about 0.84 mm long, is light yellow to orange-yellow with paler edges.[1][3][2]
- Eggs, fixed by a tiny knob at the base into the underside of the leaf, start creamy and translucent and turn gray as they age.[3][2]
- The insects feed mainly on the undersides of leaves, so turn leaves over to look for them.[2][1]
Look-alikes
| Look-alike | How to tell them apart |
|---|---|
| Greenhouse whitefly | Last-stage greenhouse whitefly nymphs carry very long waxy filaments and a waxy fringe, while azalea whitefly nymphs and pupae have no wax secretions at all.[4][3] |
Where it lives
Carried around the world wherever azaleas grow, it was first recorded in the United States in 1910 on plants shipped from Holland. It occurs in all the southeastern states, and Rutgers' nursery IPM program covers it in New Jersey.[3][2]
Biology and life cycle
It feeds on all species and cultivars of azaleas, and Rutgers adds rhododendrons, especially those with hairy leaves.[3][1][2]
Nymphs spend the winter on the leaves. Adults emerge in spring (early spring in North Carolina) and females insert their eggs into the undersides of new leaves.[3][2]
Crawlers settle, push their threadlike mouthparts into the leaf and suck sap, then molt into scale-like nymphs that also feed on sap.[1][2]
Rutgers gives timing windows for three generations in New Jersey, in growing degree days (base 50 F): about 448 to 700 for the first, 1,250 to 1,500 for the second and 2,032 to 2,150 for the third.[2]
Little is known about its life cycle, which is presumed to be much like that of other whiteflies.[3]
Damage and signs
- Sap feeding on the leaf undersides can make leaves yellow and curl and drop early, and infested shrubs become unthrifty.[2][1][3]
- Crawlers, nymphs and adults all excrete honeydew. Sooty mold grows in it and can turn azaleas dark, almost black, and a heavy coat of mold may harm the shrub by blocking light from the leaves.[1][2]
Health risk
The extension sources describe it only as a pest of azaleas and rhododendrons and mention no risk to people or pets.[1][3][2]
Control
Prevention
Reduce stress on shrubs and improve air circulation between plants.[2]
Traps and physical control
Rutgers lists yellow sticky traps for the adults and syringing, which UC IPM describes as water sprays that dislodge adult whiteflies.[2][4]
Biological control
Tiny parasitic wasps often attack the nymphs, and lady beetles, lacewings and predatory mites also feed on whiteflies. Rutgers notes that the contact and systemic insecticides on its list will harm non-target species.[1][2]
Pesticides
Horticultural oil is moderately effective and also helps weather away the sooty mold. NC State and Rutgers suggest one thorough treatment in fall and another in spring after new growth emerges. Don't spray oils, soaps or other insecticides on brand-new, tender foliage.[1][2]
Pyrethroids and imidacloprid are also labeled for whiteflies in home landscapes. Pyrethroids are very toxic to fish, so keep them away from pools, ponds and streams; Rutgers' longer product list is meant for licensed professionals.[1][2]
Common questions
- What are the tiny white moths that fly up from my azaleas?
- If they come off azaleas, they are likely azalea whiteflies. They are about 1/16 inch long and snow white, and clouds of them take off when a heavily infested shrub is disturbed.[1][2][3]
- Why are my azalea leaves turning black?
- Azalea whiteflies excrete sticky honeydew, and black sooty mold grows on it. A thorough spray of horticultural oil helps control the whiteflies and weather the mold away over time.[1]
- When should I treat azalea whiteflies?
- Plan one thorough treatment in fall and another in spring after the new growth has emerged, and avoid spraying while leaves are brand new and tender.[1][2]
Sources
- NC State Extension, “Azalea Whitefly (J. Baker, PDIC factsheet).” content.ces.ncsu.edu/azalea-whitefly (accessed 2026-11-09)
- Rutgers University, Nursery IPM program, “Azalea Whitefly (Pealius azaleae) (Nursery IPM).” sites.rutgers.edu/nursery-ipm/azalea-whitefly/ (accessed 2026-11-09)
- University of Minnesota, Department of Entomology, “Azalea Whitefly (Greenhouse & Nursery Insect Pest ID, V. Krischik; adapted from NC State AG-136).” ncipmhort.cfans.umn.edu/sites/ncipmhort.cfans.umn.edu/files/2022-03/Azalea_Whitefly.pdf (accessed 2026-11-09)
- University of California Statewide IPM Program, “Pest Notes: Whiteflies (UC ANR Publication 7401).” ipm.ucanr.edu/home-and-landscape/whiteflies/ (accessed 2026-11-09)
- iNaturalist, “Pealius azaleae taxon page (order and family).” www.inaturalist.org/taxa/380398 (accessed 2026-11-09)