Azalea: Botrytis petal blight

categories: Azalea Azalea Diseases Ornamentals Shrubs

revision date: 2024-06-05 02:07

Botrytis shoot blight on rhododendron.
Botrytis shoot blight
Photo by: R.S. Byther


Botrytis petal blight is a fungal disease typically found in early spring. Symptoms of infection include brown, water-soaked spots on the leaves, and masses of gray-brown spores which form on infected tissues. Botrytis petal blight often occurs after the plant is injured or stressed.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Good air circulation is essential. Space plantings to reduce humidity and allow good air flow.
  • Avoid overhead watering.
  • Prune out infected tissue, making cuts into healthy wood and disinfecting pruning tools between cuts.
  • Clean up and destroy any diseased material beneath plants.
  • Remove faded flowers and yellow leaves from plants.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

Application interval varies by label. Best when used with cultural controls. Copper and chlorothalonil products may discolor blooms.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.