Covering blueberry bushes in winter can help young plants, container specimens, or marginally hardy cultivars survive extreme cold snaps and drying winds. For established bushes already suited to your climate, winter covers are usually unnecessary and may trap moisture, encourage disease, or break branches under snow. The best approach depends on your hardiness zone, the blueberry type, the plant’s age, and the specific threat you face. When in doubt, contact your local cooperative extension office for guidance tailored to your area.