Mummy berry
Fungus (Monilinia vaccinii-corymbosi)
| Type | Fungus |
|---|---|
| Cause | Fungus (Monilinia vaccinii-corymbosi) |
| When | Bud break through bloom; mummies show at harvest. |
About
A fungal disease of blueberries that blights new shoots in spring and turns berries into hard, shriveled mummies. The mummies fall to the ground and start the cycle again the next spring.
Also called mummy berry
How to recognize it
Symptoms
In early spring, new leaves and shoots suddenly wilt, turn brown and may bend into a shepherd's crook, coated with grayish spores. Infected berries turn pink, tan or gray instead of blue, then shrivel into hard mummies and drop early.
Worse when
Cool, wet springs around bud break and bloom.
How it spreads
Mummies on the ground grow tiny cup-shaped mushrooms at bud break that shoot spores onto new leaves; spores from blighted shoots then reach flowers by wind, rain and bees.
When
Bud break through bloom; mummies show at harvest.
What to do, gentlest first
Prevention works best; most sprays only protect healthy leaves and can't cure infected ones. Always read and follow the product label.
Choose less-susceptible varieties Prevent
Bluetta, Collins, Coville and Darrow are listed as resistant, and Reka, Liberty and Olympia are suggested in the Pacific Northwest. Earliblue and Blueray are more susceptible.
Extension lists do not all agree on some varieties, such as Bluecrop and Jersey.
Bury the mummies Prevent
In late winter, before bud break, cover the ground under bushes with at least 2 inches of fresh mulch, or lightly cultivate the soil, to keep the little mushroom cups from reaching the air.
Rake up mummies By hand
Rake, sweep or collect fallen mummified berries and bury or destroy them.
Fungicide labeled for mummy berry Conventional spray
Several synthetic and a few organic fungicides are registered; protection runs from bud break, repeated every 10 to 14 days, through the end of bloom. Once flowers are pollinated, no new fruit infections happen.
The sources used here do not name home-garden active ingredients; ask your local Extension office. Spray in the evening to protect bees and follow the label.
Plants it affects
Sources
Planting dates and advice are general guidance; check with your local Cooperative Extension office for your area.