bee-keeperWinter does not kill bees — poor preparation does. A colony that goes into winter strong, with young bees, healthy, and with enough food will survive hard frosts. The mistakes are made in August and September, and the consequences only show up in March. That makes wintering perhaps the most important job of the whole beekeeping year. Here is what a strong, well-wintered colony really needs.
A strong colony and a young queen
The colonies that winter best are those with plenty of young bees and a queen no more than a year or two old. Winter bees are physiologically different: while a summer forager wears out in weeks, a winter bee lives for months and keeps the cluster warm until spring. So the goal is to have many young bees by autumn — which means a queen that laid well in late summer and a colony that is not exhausted. As a rough guide, a colony going into a temperate-climate winter should densely cover at least five to six frames in October; anything weaker is a candidate for uniting with a neighbour colony. Two decent colonies united winter far better than two weak ones apart.
Beat varroa first
The most common cause of winter losses is not the cold — it is varroa. Mites that build up in late summer feed on exactly the generation of winter bees that has to survive until spring, and the viruses they transmit shorten those bees' lives just when longevity is everything. So the varroa treatment is done in time, before the winter bees hatch (usually late summer / early autumn, right after the last harvest), and an extra treatment in the broodless period (oxalic acid, late autumn / early winter) cleans up the remaining mites. Count mites after the summer treatment to confirm it worked — a varroa tracking log that pairs each treatment with a follow-up count catches a failed treatment while there is still time to repeat it. Without this, everything else on this page is wasted.
Enough food — of the right kind
A colony needs enough stores to survive from the last forage to the first spring nectar. In temperate climates that means roughly 15–20 kg of capped stores, and up to 25 kg where winters are long — judged by hefting or weighing the hive in early autumn, not by glancing at the top bars. The rule is: a little too much beats too little, because unused stores carry over to spring. Winter feeding is done in time, with thick 2:1 syrup or fondant, while it is still warm enough for the bees to process and cap the food. Late feed the bees cannot cap stays damp and spoils.
- Feed in time — while the days are warm and the bees active
- Make sure the honey/syrup is capped before the cold
- Leave some pollen/bee bread too, for the first spring brood
Damp is more dangerous than cold
Bees tolerate cold if they are dry and fed — but damp kills them. The winter cluster produces heat and water vapour; if that vapour condenses on a cold cover and drips back onto the bees, the colony is chilled and fails. Good ventilation is therefore key: a slightly sloped roof or top ventilation so moist air escapes, the hive sheltered from wind but not sealed airtight. Insulation helps — especially above the cluster, where warm moist air meets the cover — but never at the expense of airflow.
Protection from mice and wind
In autumn, narrow the entrance or fit a metal mouse guard — once a mouse gets in, it builds a nest and wrecks the comb. Place hives so they do not face the north wind, tilted slightly forward so water runs out of the hive, and stable so the wind cannot move them. If your area gets strong wind or snow, a windbreak or shelter helps a lot.
Winter quiet and silent checks
Once you have wintered a colony, leave it in peace — every opening in the cold chills the cluster and burns precious food. Winter checks are quiet and from the outside:
- Listen, or tap the hive gently — a soft, even hum means the cluster is alive
- Judge the stores by lifting the back of the hive ("hefting") or weighing it
- After snow and ice, clear the entrance so the bees can take a cleansing flight
- Use the broodless period for the final varroa treatment
Late winter: the hungriest weeks
Most starvation losses happen not in the deep cold but in February and March, when the queen resumes laying and the colony's consumption jumps — right when stores are at their lowest. A colony can also starve centimetres from food if a long cold spell pins the cluster away from it. So from midwinter on, heft the hives regularly, and if one feels light, lay a 1–2 kg slab of fondant directly over the cluster (never liquid syrup in the cold). When the first warm days bring the cleansing flight, watch the entrances: colonies that fly strongly are through the worst. The first full inspection still waits for a calm day of around 15 °C.
Let the app remind you
Wintering is a sequence of steps that have to happen at the right time — and it is easy to skip one. In the bee-keeper app, seasonal reminders walk you through the autumn jobs, and for each hive you record how much food you gave and when you treated for varroa, so in spring you know exactly what each colony is coming out of winter with.
Frequently asked questions
How much food does a colony need for winter?
Roughly 15–20 kg of capped stores in temperate climates, up to 25 kg where winters are long. Judge it by hefting or weighing the hive in early autumn and feed the difference while it's still warm — slightly too much is always better than too little.
Should I insulate the hive for winter?
Insulation above the cluster helps because it stops condensation dripping back onto the bees, and a wind-sheltered site matters more than thick walls. Whatever you add, never seal the hive airtight — moist air must be able to escape.
When is it too late to feed syrup?
Once days are too cold for the bees to take, invert and cap it — in most temperate areas that means syrup feeding ends by mid-autumn. After that, the only safe emergency feed is fondant placed directly over the cluster.
How do I know in midwinter whether the colony is alive?
Put your ear to the hive (or use a tube) and listen for a soft, even hum, or tap gently and listen for the brief rise in sound. Check weight by hefting. Don't open the hive in the cold — an opened cluster loses heat it can't spare.