Blueberry: Mummyberry

Biology

Mummyberry is a fungal disease affecting blueberry flowers, leaves, twigs, and fruit. In the spring, flower and shoot buds are infected. The affected tissues turn brown and withered. A grayish to brown growth of fungal spores may appear on the infected tissues. These spores are easily spread to the blossoms by wind, rain, and pollinating insects, causing infection of the fruit. Diseased fruit appear normal until nearly full-sized, although infected green berries may show a white fungal growth around the seeds when sliced open. Infected berries may be somewhat pumpkin-shaped and turn white, tan, or pinkish as they approach maturity. They often drop from the plant before healthy fruit matures. The fallen berries harden and “mummify”. The fungus overwinters in the fallen mummies.

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 resistant varieties. ‘Berkeley’, ‘Bluetta’, ‘Concord, ‘Darrow’, ‘Dixie’, ‘Jersey’, ‘Lateblue’, ‘Pemberton’, and ‘Rubel’ are resistant or moderately resistant to leaf, shoot, and fruit infections. Other varieties have shown resistance, but have not been tested in the Pacific Northwest.
• In small plantings, clean up and destroy mummies.
• Cultivate to bury the mummies in the fall. In the spring rake the soil to disturb and to destroy the developing fungus.

Chemical Management

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

• Products containing chlorothalonil are for use on foliage and blossoms from budbreak through early bloom.
• Scout for fruiting bodies (apothecia) and time first application to coincide with their development.

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]
• Captan 50% WP Fruit and Ornamental
  Active ingredient: captan [EPA registration number: 4-459]
• Hi-Yield Vegetable, Flower, Fruit and Ornamental Fungicide
  Active ingredient: chlorothalonil [EPA registration number: 60063-16-7401]
• This list may not include all products registered for this use.

Additional Images