Spider mites
Almost invisible without a hand lens. Yellow-green to red-orange specks running along the underside of each leaflet. The 7 to 9 leaflets radiating from each umbrella spoke create dozens of hiding surfaces, and indoor heated air through winter triggers a population boom.
Pale tiny pale dots across the upper leaflet faces and fine webbing strung between leaflets at the umbrella center. Heavy infestations bronze the foliage and cause leaflets to drop one by one, defoliating the umbrella shape that gives the plant its appeal.
Shower the canopy weekly for 3 weeks
Move the plant to the shower. Spray cool water on the underside of every leaflet for 60 seconds, working through the dense umbrella canopy and tilting branches so water reaches the spoke centers. Mites can't reattach quickly when knocked off. Repeat weekly for 3 weeks.
Neem oil at lights-out, every 5 days for 3 rounds
Mix 2 tablespoons cold-pressed neem oil and 1 teaspoon dish soap per gallon of water.
Spray top and bottom of every leaflet at lights-out, lifting branches to coat the leaflet undersides where mites cluster.
Repeat every 5 days for 3 rounds. That covers the full egg-to-adult cycle.
Raise humidity above 50%
Run a humidifier near the plant for 50 to 60% relative humidity through winter. Dwarf umbrella tree comes from humid Southeast Asian forests and prefers the moisture anyway. Hot dry indoor heating is the climate mites need to breed fast on the dense leaflet canopy.
