Poor overwintering success
Winter colony losses averaging 30-40% annually are a major challenge for beekeepers in temperate climates. Losses typically stem from varroa mites and associated viruses, inadequate food stores, moisture buildup, and weak colony populations heading into cold months.
- Treat for varroa mites in late summer and fall5
Apply varroa mite treatments in August-September to ensure the generation of "winter bees" (long-lived bees raised in fall) develops with low mite pressure. Colonies with mite loads above 2-3% at this stage produce weakened winter bees that often die before spring.
📌 best practice4/16/2025, 9:22:02 PM
🛠️ Mite treatment (oxalic acid vaporizer, formic acid strips, or amitraz strips), alcohol wash kit or sugar roll supplies, gloves, hive tool
- Ensure adequate honey stores or supplement feed4
Verify colonies have 60-90 lb (27-41 kg) of stored honey heading into winter, depending on climate severity. Colonies that run out of food before spring nectar flows begin will starve -- starvation is one of the top three causes of winter loss.
📌 best practice📌 diy📌 low cost4/16/2025, 9:22:02 PM
🛠️ Bee feeder (top feeder or frame feeder), fondant or sugar bricks for winter feeding
- Winterize hives before cold weather arrives5
Prepare hives in late fall by insulating, managing ventilation, and protecting against wind and pests. Colonies that are properly winterized retain heat more efficiently and avoid the moisture buildup that kills more colonies than cold itself.
📌 best practice📌 diy4/16/2025, 9:22:02 PM
🛠️ Entrance reducer or mouse guard, insulation board or moisture quilt, hive wrap, hive tool
- Combine weak colonies to build winter-ready strength4
Assess colony strength in September and merge any colonies covering fewer than 6-8 frames of bees into stronger units using the newspaper method. A colony needs at least 20,000-30,000 bees to maintain the winter cluster temperature of 34-35°C (93-95°F) at the core.
📌 best practice📌 free4/16/2025, 9:22:02 PM
🛠️ Newspaper, hive tool