Winter feeding · how much, when, and why August decides it

There is a moment in the beekeeping year when things seem to go quiet. The honey is extracted, swarming season is over, the hives stand still. That is exactly when the work begins that decides whether your colony is still alive in March.

Winter feeding looks simple: sugar in, done. But the two things that go wrong most often are too little and too late, and you notice both only when they can no longer be fixed.

Why August and not October

A colony can only process feed while it is warm enough and there are enough bees to thicken and cap it. Syrup given in October often stays uncapped in the comb. Uncapped feed attracts moisture and can ferment, and fermenting feed causes gut problems in bees that cannot leave the hive for months.

On top of that, the bees processing the feed are the summer bees. They live six weeks. The winter bees born in September and October need to conserve — their job is to survive until March, not to work.

Hence the rule of thumb: start as soon as the last honey is off, and be finished by mid-September. In a warm autumn you can stretch that to the end of September; beyond that you are gambling.

How much a colony needs

This depends on hive type, colony strength and region. As a guideline for the Netherlands and Belgium:

• Simplex or national hive, strong colony · 15 to 18 kg of feed
• Ten-frame brood box · 12 to 15 kg
• Smaller or young colony · 10 to 12 kg
• Six-frame or nucleus · 8 to 10 kg

That is the weight of feed, not of sugar. One kilo of sugar yields roughly 1.2 kg of feed once dissolved. For 15 kg of feed you therefore need about 12.5 kg of sugar.

Honey still in the hive counts towards this. A colony with two full frames of stores does not need another 15 kg.

Dissolving sugar yourself or buying ready-made

Both work. The difference is convenience and cost.

Dissolving yourself · ordinary white granulated sugar, three parts sugar to two parts water (3:2) for autumn feed. That is a thick syrup the colony barely has to thicken. Warm water dissolves faster, but do not boil it: at high temperatures HMF forms, a substance harmful to bees.

Ready-made fondant or syrup · more expensive per kilo, but no stirring and a stable composition. For someone with a few colonies and little time, that often outweighs the price difference.

Do not use cane sugar, soft brown sugar, honey of unknown origin or kitchen leftovers. Cane and dark sugars contain compounds bees cannot digest, and foreign honey can carry American foulbrood.

How to give it

Feed in portions of 3 to 5 kilos at a time, a few days apart. A colony given twenty kilos at once stores it all in the brood box and leaves the queen no room to lay. Right now she needs to keep producing winter bees.

Use a feeder above the colony, with a lid on it. Never feed openly in the garden or beside the hive. In August that is asking for robbing: wasps and other colonies smell sugar from a distance and head straight for it.

Feed towards evening if you can. Flight activity has stopped by then and things stay calmer at the entrance.

The sequence that works

1.Last honey off · late July or early August

2.Varroa treatment · immediately after, because winter bees infested as larvae become weak winter bees

3.Feeding · as soon as treatment is finished, in portions

4.Mid-September · finish feeding

5.October · do nothing, only check the entrance is clear

6.December · residual treatment with oxalic acid on the smallest cluster

That order is not arbitrary. Treating after feeding means introducing substances into a colony that has just laid down its winter stores, and formic acid at high temperatures next to a full hive is a poor combination.

Common mistakes

• Giving too little because the colony "seems to have enough". What is there in August is not what remains in February. February and March are the months colonies starve, not December.
• Starting too late. Feed that never gets capped is feed you might as well not have given.
• Everything at once. The queen then has no room left to lay winter bees.
• Open feeding. Causes robbing, and a robbed-out colony will not make it.
• Forgetting to weigh. Lift the hive from the back. If it feels light, it is light. That is more accurate than guessing from how full it looks.
• Feeding without treating first. Varroa pressure must come down before the winter bees are born, not after.

How to check whether it is enough

The simplest method is lifting. Take hold of the back of the hive and lift it a few centimetres. A well-provisioned colony feels heavy — heavier than you expect.

If you want to know more precisely, put scales under the hive or use a luggage scale on the back edge and double the result. Note the weight in October and again in February; the difference tells you more about your own region than any rule of thumb.

What comes after

Once fed, you are done. Mouse guard on, entrance reduced, and otherwise leave them be. Every time you lift the lid in October or November it costs the colony warmth it cannot spare.

The temptation to look is strong, certainly in your first winter. But a colony that is well fed, treated against varroa and standing dry does not need you any further.

Frequently asked questions

How much sugar do I need per colony?

For 15 kg of winter feed you need roughly 12.5 kg of sugar, since dissolved sugar yields about 1.2 kg of feed per kilo. A strong colony in a full-size hive comes to 15 to 18 kg of feed; a smaller colony or nucleus to 8 to 12 kg.

When am I too late to feed?

Mid-September is the safe limit; in a warm autumn you can continue to the end of September. After that it is too cold and there are too few summer bees left to thicken and cap the feed. Uncapped feed attracts moisture and can ferment.

Can I use cane sugar or brown sugar?

No. Use ordinary white granulated sugar. Cane and dark sugars contain compounds bees cannot digest and cause gut problems during winter, when they cannot leave the hive to defecate.

Should I treat for varroa first or feed first?

Treat first. Winter bees are born in August and September, and larvae infested then become weaker winter bees. Formic acid at high temperatures next to a freshly filled hive is also a poor combination.

Why feed in portions rather than all at once?

A colony given everything at once stores it in the brood box and leaves the queen no room to lay. In this period she needs to keep producing winter bees. Portions of 3 to 5 kilos a few days apart work better.

How do I know my colony has enough?

Lift the hive from the back. A well-provisioned colony feels clearly heavy. For more precision, weigh with a luggage scale on the back edge and double the result. Note the weight in October and again in February; that difference says more about your region than a general rule.

To close

Overwintering is not complicated, but it is unforgiving: what you get wrong in August cannot be put right in November. Enough feed, given in time, after a treatment that brought varroa pressure down. That is all there is to it.

How do you go about it, and how many kilos do you overwinter with? Share it on the forum under Bee Health & Diseases — the numbers differ by region and hive type, and others learn from that.