Hoya Powdery Mildew & Begonia Fungus Gnats: Dual Treatment

Two plants, two distinct issues:

Hoya: White Powdery Coating = Powdery Mildew

• Remove heavily coated leaves.
• Spray with fungicide (sulfur, neem oil, or potassium bicarbonate).
• Improve air circulation; avoid wet leaves.

Begonias: Tiny Flies in Soil = Fungus Gnats

• Larvae feed on roots in wet soil.
• Let soil dry 1–2 inches deep between waterings.
• Apply Bacillus thuringiensis israelensis (Mosquito Bits) to soil or use yellow sticky traps.

General Fix

Both problems stem from excess moisture. Water less, ventilate more.