Viburnum: Leaf spot

Biology

Various fungi cause leaf spot symptoms on viburnum. The spots are typically necrotic brown spots of varying sizes. At least one bacterial leaf spot is also common.

Management Options

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

Non-chemical Management

Select non-chemical management options as your first choice!

• Plant in full sun.
• Space plants and prune to provide good air circulation.
• Remove and destroy infected leaves and shoots.
• Rake and destroy fallen leaves.
• Leaf spot diseases should be accurately diagnosed before further action is taken. Consult your county Extension agent or WSU Master Gardeners for assistance.

Chemical Management

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

• Fungicides may be applied to protect new growth or at first sign of disease.
• Homeowners should not make foliar applications to trees over 10 ft tall.
• Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Approved Pesticides

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

• Bonide Copper Fungicide Spray or Dust RTU [Organic]
  Active ingredient: basic copper sulfate [EPA registration number: 4-58]
• Bonide Fung-onil Multi-Purpose Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 60063-9-4]
• Bonide Liquid Copper Fungicide Concentrate/Organic Gardening
  Active ingredient: copper octanoate [EPA registration number: 67702-2-4]
• GardenTech Daconil Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 67572-82-71004]
• Monterey Liqui-Cop Copper Fungicidal Garden Spray
  Active ingredient: copper-ammonia complex [EPA registration number: 54705-7]
• 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.