Rose: Botrytis bud and twig blight

Biology

Botrytis can infect stems and flowers, including stubs left from pruning or flower removal. Infected tissues are usually covered with a fuzzy, gray-brown growth. Infected flower buds may not open, and can show sunken, smooth, grayish spots on the bud and flower stem. Sunken, dead areas may develop on the canes. Infection is worst during cool, wet weather.

Management Options

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

Non-chemical Management

Select non-chemical management options as your first choice!

• Remove all infected portions of plants as soon as the first symptoms appear. This reduces spread of the disease.
• Clean up and destroy all dead plant materials.
• Increase air circulation in plantings by proper spacing and pruning.
• Avoid overhead watering.

Chemical Management

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

• Use as a foliar spray but focus on cultural controls.

Approved Pesticides

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

• Bonide Fung-onil Multi-Purpose Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 60063-9-4]
• Bonide Infuse Systemic Disease Control Lawn and Landscape
  Active ingredient: thiophanate methyl [EPA registration number: 53883-183-4]
• GardenTech Daconil Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 67572-82-71004]
• Ortho Max Garden Disease Control Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 239-2522]
• This list may not include all products registered for this use.