White Powder on African Violet Blooms: Powdery Mildew or Spider Mites?

Holly's African violet in a cool north window developed white powder on blooms (not leaves). She wondered if powdery mildew affects flowers alone.

Differential Diagnosis

• Powdery mildew: Usually affects leaves too; thrives in high humidity
• Spider mites: Webbing on flowers resembles powder; check leaf undersides for mites
• Botrytis: Fungal flower blight; remove affected blooms

Immediate Actions

Remove all affected flowers. Increase air circulation. Reduce humidity. Try 50/50 milk-water spray on remaining blooms. Contact AVSA (avsa.org) for definitive diagnosis—flower-only powder is unusual.

Prevention

Avoid wetting flowers. Space plants for airflow. Monitor humidity.