Winter Feeding and Mite Teatment

Through winter the bees are all busy keeping warm, clustered in their hives away from the prying eyes of beekeepers. Barring a bit of hardware maintenance, woodwork and renewing Beekeeping Association subs there isn't much for Beekeepers to be doing. However there are two bee related tasks still to be done: mite treatment and Winter feeding.


The mite treatment as with every other year is an organic acid treatment which kills off a huge proportion of the varroa mites in the hive. There's a couple of options but most beekeepers seem to be using an Oxalic Acid solution. It's easy to make, just dissolve 35g Oxalic Acid Dihydrate in one litre of sugar syrup -most sources say to use 1:1 syrup but 2:1 syrup has been used by some. The hive is then opened and the syrup trickled between the frames directly onto the bees. As the bees move about the solution gets distributed over the whole colony and onto the mites. It takes 5ml per seam for a National hive and by my calculations 6.6ml per seam for a Commercial. It's only effective when the mites are actually on the bees though so needs to be done then the colony is broodless. If there's brood most of the mites will be in the comb with new larvae and the oxalic solution won't reach them. Waiting for a long enough cold snap took a while but I treated my colonies about a fortnight ago.

Mite treating time

Oxalic solution is very cheap and easy to make at home, unfortunately it's no longer legal for beekeepers to do so. Last year a firm called Api-Bioxal registered it as medical product so now any treatment with Oxalic Acid needs approval from the Vetinary Medicines Directorate. This means you can't just whip up your own solution or buy it from just anyone anymore, you need to buy the approved and expensive VMD approved product. The approved Api-Bioxal currently costs £10.99 for a 35g  sachet of what is clearly Oxalic Acid Dihydrate, if you shop around and source your own >99.5% pure Oxalic Dihydrate you get about half a kilo for that price. So the cost of treating my 8 hives with Api-Bioxal comes to about ninety quid whereas using other Oxalic Dihydrate I'd be paying under a fiver. Not that I'm suggesting anyone does ..obviously I used the super expensive pricey approved stuff and the photo above shows a bottle of lemon barley water I was drinking at the time and the syringes were just so I could drink it through the veil of my beekeeping jacket. Honest.

Can see the roughly round shape of the cluster here.

I've not seen my bees for a long time, what with it being winter and all but opening hives in Winter is quite different to Summer. In the summer bees tend to be distributed allover the comb in the brood box but in winter they form a rounded cluster and when you remove the crownboard you can clearly see the shape of it. All being well the cluster moves in the hive using stored food from the combs.

When I was doing the treatment I found four of my colonies are still very densely populated with huge clusters whereas two are like the one above where there's been some of the expected die back and two are looking very low on numbers. The two colonies that are low on numbers may struggle to generate enough heat so I whilst I've  so far left the mesh floors open with those two I closed them to try an conserve heat -I very much doubt they'll make it through Spring but shall wait and see.

You can order anything, as long as it's sugar.

In Winter hives can be running a little low on stores -especially big strong colonies that haven't experienced much die back  through Winter. Because of that it's fairly common practice to give the colonies a little food top up. Bees won't take syrup when it's cold so instead the beekeeper can give them dry sugar or fondant. In previous years I've made candy boards which are effectively huge square sugar lumps covering the top of the hive so the bees have access to emergency food wherever they are in the colony. I had planned to make newer shallower candy boards but never got round to it so this year I've gone back to fondant again.

Fondant can be given in a block, as it comes from the packet, placed above the feed hole in a crownboard with a plastic food tub above it which I've done previously. This time I decided to just cut the Dr Oetker Ready to Roll Icing very thinly and place it above the frames in the small gap between the frame tops and the crownboards. With the fondant in place the crownboards, insulation and roofs were quickly put back in place so the bees could get back to warming the air in there.

Bees making cleansing flights, must be quite a relief for them.

On Monday just gone I popped to the out apiary and was able to see bees making cleansing flights although according to my weather app it was only 7 degrees Celsius. It's been a fairly warm winter so far, which isn't great for the bees. In a cold winter they're less active and cluster tighter using less food, when it's warmer they're more active which means using up more energy and depleting food stores faster. In early Spring I'll need to check how much they've got left as that's the time they're at most risk from starving.