Common Blueberries pests

Spotted wing drosophila is a small vinegar fly whose females lay eggs in ripening and ripe berries, leaving soft, leaking fruit with tiny white maggots inside. Blueberry maggot, a native fruit fly, and the cherry and cranberry fruitworms also tunnel into berries, causing premature coloring, shriveling, and webbing near the stem cluster. Japanese beetles skeletonize leaves, aphids cluster on new growth and can spread viruses, and birds are often the single largest source of fruit loss, stripping bushes as berries turn blue.

Common diseases

Mummy berry, a fungal disease, first blights and wilts new shoots and flower clusters in spring, then infected berries turn tan, shrivel, and drop as hard mummies. Botrytis gray mold and anthracnose rot the flowers and ripening fruit, with anthracnose showing salmon-pink spore masses on soft berries in wet weather. Phomopsis, Fusicoccum, and Botryosphaeria cause twig blight and stem cankers that wilt individual canes, Phytophthora root rot appears as stunting and dieback in soggy soil, and viruses such as blueberry scorch and blueberry shock cause sudden flower and leaf blighting.

Prevention

Plant in well-drained, acidic soil (roughly pH 4.5 to 5.5) since wet roots invite Phytophthora, and choose disease-tolerant cultivars suited to your region. Space bushes for good air movement and prune out old, weak, and crossing canes each dormant season to open the canopy and speed drying. Remove and destroy mummified berries and fallen fruit, since the mummy berry fungus overwinters in this debris, and water at the base with drip or soaker lines rather than wetting the foliage and fruit.

Organic control

Bird netting or a covered cage installed just before berries begin to color is the most effective and least-toxic defense against your biggest fruit thief. For spotted wing drosophila and fruitworms, harvest promptly and often, keep the ground clear of dropped fruit, and use OMRI-listed spinosad or Bt for caterpillar fruitworms, always following the product label. Hand-pick Japanese beetles into soapy water in the morning, treat aphids with insecticidal soap or neem, and where labeled for blueberries, apply a fungicide such as copper or lime sulfur for mummy berry and canker control, reading and following all label directions.

Scouting & monitoring

Scout at bud break and bloom for wilted, browning shoot tips that signal mummy berry, and pinch out strikes as you find them. As fruit starts to color, hang red sphere or vinegar-baited traps to detect blueberry maggot and spotted wing drosophila so you can time your harvest and controls. Check ripening clusters weekly for soft, leaking, or webbed berries, inspect new growth for aphids, and watch canes through summer for sudden wilting that points to canker or stem blight.

Tips

Frequent, clean harvest plus removing every dropped and mummified berry breaks the life cycle of the worst fruit pests and diseases without chemicals. If you only invest in one control, make it good bird netting timed to fruit coloring, because it protects the whole crop at once.

General home-garden IPM guidance, focused on prevention and least-toxic control. Always read and follow the product label for any pesticide, including organic products. Page updated Aug 4, 2026.