Controlling Whitefly Larvae on Bougainvillea in Mediterranean Climates: Horticultural Oil Treatment

Cottony Masses on Bougainvillea in Spain

The white cottony clusters are whitefly larvae wrapped in wax.

Prune off heavily infested branches.
Spray remaining foliage with horticultural oil (e.g., Ultra‑Fine Oil, Organicide)—not dormant oil.
Apply in late afternoon; rinse next morning if sun is intense.
Repeat weekly until no new cotton appears.

Consistency breaks the whitefly cycle.

Tropical Plants: Clarifying T.S.O. and S.O. Horticultural Oil Designations; Stemmadenia (Milky Way Tree) White Underside Fungus: Downy Mildew Suspect; Black Threads in Spalted Elm: Fungal Mycelia, Not a Hazard; Fungus Gnats in Dwarf Banana Office Plants: Dry Soil and Fly Paper; Pine Green/Gray Fungus: Lichens, Not Disease; Persistent Fungus Gnats in Houseplants: Cultural and Biological Controls; Tomato Early Blight and Gardener Allergies: Fungicide Treatment and Personal Protection; Thick White Fungus Around Ferns and Roses: Nuisance or Threat?; Black Honeycomb Fungus in Flower Bed: Slime Mold or Something Worse?; Strange Fungus in Antique Furniture: Identification and Safety

Garden Articles

Plants