Getting a colony through winter mostly comes down to a few things done well: a healthy, well-populated colony, enough food, controlled mites, a hive that is not too big, and protection from damp and pests. This checklist walks through them in roughly the order most beekeepers tackle them.
Winter conditions vary a great deal between regions, so treat the details below as general guidance. Your local beekeeping association or national apiary service is the best source for timings and treatment rules where you live.
Why winter prep starts in late summer
Winter preparation does not start when the weather turns cold. The bees that carry a colony through winter are raised in late summer and early autumn, and the food they will eat is stored before the flow ends. Many beekeepers begin thinking about winter in August and finish in autumn. Our guide to August beekeeping covers the late-summer end of this timeline.
A seasonal checklist
A rough order of work for the northern hemisphere (shift the months for your climate):
- Late summer: inspect thoroughly, monitor and treat varroa, finish honey harvest, and decide how much honey to leave.
- Early autumn: confirm the queen is laying, feed if stores are light, and unite or deal with very weak colonies.
- Before cold weather: reduce the hive to the space the bees can use, remove the queen excluder, fit entrance reducers or mouse guards, and sort out ventilation.
- Winter: monitor from the outside, heft the hive, and add emergency food only if needed.
Check the colony is worth wintering
A strong colony with a good, young queen and plenty of bees has the best chance. A very small colony, a drone-laying or failing queen (what happens when a queen is lost), or a colony with serious disease is much less likely to survive. Beekeepers often choose to combine a weak colony with a stronger one in autumn rather than hope it improves. If you are unsure, ask an experienced local beekeeper to look at it with you.
Control varroa first
Varroa mites weaken the long-lived winter bees, and a colony that goes into winter with high mite numbers often fails even when it has plenty of food. Monitor mite levels in late summer (for example with an alcohol wash, sugar roll or sticky board) and treat according to the products approved and recommended in your area. Always follow the label and timing instructions, and avoid treating while honey supers are on.
Food stores
Bees live on stored honey through the cold months. How much a colony needs depends on its size, your climate and how long winter lasts. Sources commonly suggest figures in the range of 60 to 100 pounds (roughly 27 to 45 kg) of stores for a full-size colony in cold climates, with less needed in milder areas, but your local association can give a more reliable number.
- Heft the hive. Gently tilting the back of the hive gives a feel for weight (see how much a bee hive weighs). A hive that feels light in autumn probably needs feeding.
- Feed if needed. Autumn syrup is usually mixed thicker than spring syrup, often 2 parts sugar to 1 part water by weight, because the bees have less work to do removing water. Feed early enough that the bees can store and cap it before it gets cold.
- Leave honey. If you harvest, leave enough in the hive rather than relying only on sugar. See honey extraction for harvesting.
- Emergency food. Fondant, a sugar board or dry sugar placed above the cluster can help prevent starvation in late winter. Bees can starve with food a few centimetres away because the cluster cannot break to reach it in cold weather.
Reduce and arrange the hive space
Bees heat the cluster, not the whole box. Removing empty supers and unused boxes reduces the space the colony has to manage. Make sure the remaining frames hold food within reach of where the cluster will sit.
Take off the queen excluder before winter. If left in place, the cluster can move up through the hive eating honey and leave the queen below the excluder.
Moisture and ventilation
Bees produce moisture as they burn honey. In a cold hive that moisture can condense, encourage mold and drip onto the cluster, which many beekeepers consider a bigger threat than cold itself. Good ventilation, a slight forward tilt so condensation runs to the front, and sometimes an absorbent layer or quilt box above the frames are common ways to manage this. Do not seal the hive up completely.
For how the cluster generates heat and what temperatures it holds, see bee hive temperature in winter.
Pests and weather protection
- Mice: Fit mouse guards or a reducer before mice look for winter shelter, usually autumn.
- Woodpeckers and wind: Where these are a problem, wire or a windbreak may help. Strap hives down against storms.
- Standing water: Keep hives off wet ground, on a stand.
- Insulation: Wrapping or insulating (see insulated hive plans) is common in colder regions, but it should not block ventilation.
Winter monitoring
Avoid opening the hive in cold weather, since this can chill the colony. Instead:
- Look at the entrance and clear dead bees from the landing board.
- Listen for a hum by gently putting an ear to the hive wall.
- Heft the hive to judge remaining stores.
- Check that snow or debris is not blocking the entrance.
If you suspect a colony is starving on a mild day, add fondant or sugar quickly and close up again.
Frequently asked questions
How cold is too cold for bee hives?
There is no single figure. Well-prepared colonies in many cold regions survive prolonged freezing temperatures, because the cluster generates its own heat. Problems are more often damp, starvation, mites or a small colony than cold alone.
Can a hive survive winter without a queen?
Generally no. Without a queen, no new winter bees are raised and the colony usually dwindles through winter. A queenless colony found in autumn is often combined with a queenright one. See whether hives die in winter for more on why colonies fail.
What comes after winter?
When the weather warms, check stores again and feed if needed. Our guide to spring feeding covers what to do.