Fungus on Indoor Hibiscus Flowers: Prevention in Sunroom

Hibiscus brought indoors for winter often develop flower fungus (botrytis) due to high humidity, reduced light, and poor air circulation in crowded sunrooms.

Prevention

• Space plants for air flow; use fans.
• Water at soil level, early day; avoid wetting flowers.
• Remove spent blooms daily.
• Reduce humidity: vent windows, dehumidifier.
• Preventative copper or sulfur fungicide at bud stage (organic options available).

Cutting all buds is a last resort; cultural changes usually suffice.