A colony of bees is valuable livestock and consequently we all want our bees to go into winter well prepared - why would we not?
For bees to survive the winter you need:-
- A laying queen
- No disease issues
- Sufficient stores
- A hive in good condition
- A colony that is large enough for the hive
- Suitable location
- Protection from pests
Here's a summary:-
- A young laying queen will lay longer into the winter and start earlier in the early Spring so youth does have an advantage here. A queen going into winter in her third year is getting on a bit!
- We should always be vigilant looking for disease, however a diseased colony has a poor chance of getting through winter compared to one that is fighting fit. A good check for brood diseases is necessary - Beebase has useful information - see here. Varroa also needs to be held in check too. If you have a colony that has a suspected disease then further checks must be made. If Nosema is suspected or diagnosed then Fumidil B used to be administered but is no longer available. (A strong thymol mix is said to work - see the 'paper in 'Useful Documents').
- A national brood chamber is usually enough provided it is full and heavy with stores. However some strains of bees – notably of Italian extraction (Ligustica bees) which are generally yellower – use more stores than most others.
- Hives should be sound without leaks. Hive bases should also be strong and keep the hive off the damp ground. Weigh the roof down or possibly strap the hive to the stand to withstand the effects of high winter winds. If you don’t, then that’s your choice! A colony will probably survive for a while if tipped over and strapped together. The chances of survival are much less if the hive is scattered around with bees everywhere.
- A small colony will survive in a small hive much better than in a large hive with lots of wasted space. If you have a small colony then a large hive can be packed with insulation either side of the brood and stores area to reduce the volume the bees have to heat.
- Damp ground and excessive shade is not good, nor is a site where the wind blows a gale all the time. A little winter sun allows the hive to warm so the bees can get to/move stores and go on quick cleansing flights.
- Mouse-guards should be in place and if you have woodpeckers nearby then you may need to take precautions. Pests could include larger animals and even humans!
Food Glorious food.
At the end of the season I prefer my colonies to go into winter with a full brood chamber of stores plus a super. (Larger colonies or those that have been united late in the year stay on double brood boxes). If we leave the super over the brood chamber with a queen excluder we have several disadvantages:-
- The queen may get left behind; that is below the queen excluder if the bees move upwards. Although there's not too much likelihood of this, the possibility is still there.
- There is a large space to heat above the bees which is not good for spring build-up as they will have to work much harder to get the brood area up to the 35 degrees they need.
- With an open mesh floor, the bees may get a little wind-blown.
- Oxalic Acid treatment in the winter may be difficult as the bees will most likely be buried deep within the hive and not visible.
So this is what I do. Sometime in late September or maybe even early October – at the last quick inspection/check – I remove the super - full or part-full and place it on the hive open mesh floor and then put the brood chamber on top with NO queen excluder. The crown board goes on the top of the brood chamber. Let’s consider what has been done.
The bees are now at the top of the hive – the warmest part and they have plenty of stores to last the winter with a super of honey within their reach. It is unlikely that you'll need to mess about with fondant or candy in the Winter/Spring time. With no queen excluder there is no restriction to the queen's movements. Usually the bees are clearly visible for oxalic acid treatment in winter when the crown board is taken off. Spring build-up will be easier for the bees. The super below brood chamber reduces the effects of wind around the bottom of the hive. On top of the crown-board I place some insulation. An inch or two of celotex/kingspan or such-like will reduce the heat loss through the roof considerably and ensure that there are no cold-spots above the winter cluster where condensation might otherwise develop and drip down. Other insulation could be a layer or two of carpet or even an empty super filled with scrunched newspaper. They will all help conserve heat and with an open floor there is sufficient ventilation for the colony to give them oxygen and remove moist air. And by conserving heat, honey consumption is reduced. It is generally accepted that the amount of fungus and mold in the hive is reduced with insulation too - it's certainly my experience. Open mesh floors should be kept open and the mite-board only slid in when a mite count is being done. You may think that the bees need to be cozy inside but they give off quite a lot of water vapour. All my colonies have come through winter like this over quite a few winters. NO winter losses apart from the odd duff queen; and no isolation starvation where the bees cannot get to the food in the hive as it's too cold to move about.
A word of warning when this can fail is if there's very little stores in the brood box and the super goes underneath late. In this situation you'll have the bees at the top of the hive with a large space below them and the stores in the super underneath - too far away for them to reach.
In the spring - at the first inspection which will usually need to be quite quick - the super can be removed from under the brood chamber. Generally the supers have been pretty well empty of stores at this time. The hive can be operated for a short while with just the brood chamber (feeding may be required if light on stores but unlikely) and then the super can go on the hive, over the queen excluder when bee numbers have increased. If the queen has started to lay in the super, then put it above the brood chamber with a queen excluder between in the usual way. After 3 weeks the young bees will have emerged from the cells. Note that I usually keep the insulation on the hive all year - on most roofs it's built in now. Also see Adding a Super.