Paul brings up a very good point: what are the min temps that one can feed syrup. I typically read 55 F for the syrup, but that is referring to inside the hive and not the outside temp. So at what outside temp is the syrup still touched by the bees? The night / day fluctuations, hive config, and # of bees likely have an impact as well as the # of bees in the hive since they warm up the syrup.
Here is my recent experience:
I fed my bees last Saturday. I had similar questions / doubts as Paul shared whether it makes sense given a forecast of highs in the 40ies. My results greatly varied as described below.
I have 7 hives going into winter. I had taken off my tray feeders and wanted to extend the feeding season. I am no expert in this, but based on posts here, my readings, and my past experience I thought the following:
- some of my hives were a little lighter than I would have liked even though I always harvest only modest amounts to leave honey for the bees, so I was motivated to feed more
- the longer I feed, the longer I stimulate brood rearing (good for winter survival)
- the longer I feed, fewer honey stores will be used up in fall (I might be wrong on that)
- I had very good overwintering success my last 2 seasons, so I am mostly sticking with my management plans that worked for me lately, and that includes supplemental feeding until its too cold, even for hives that have good resources already.
Setup: All Langstroth: 3 deep or 2 deep + 1 super. I had already added a 'wicker board' aka 'brown board' on top of a 2-3 in feeder rim and I have added 1.5 in of styrofoam on top of that on some of the hives. Both act as insulators and will help to keep some more heat in the hive. Small bottom entrance + small top entrances. Not all of my cork size round box entrances are closed yet (but they probably should be).
Last Saturday afternoon, I added 1 to 2 ziplock bags with 2:1 syrup mix, food coloring, and some 'Honey B Healthy'. I checked 10 mins later and all hives had a good amount of bees on top of the bags, so they all found it quickly.
My hives are 50 min away from my residency, so the first time I checked again was yesterday afternoon.
Results: 4 of the 7 hives had emptied the bags. These hives also had a considerable amount of bees in the rim when I checked, apparently looking for more food in the bags. The other 3 hives had hardly touched the syrup and there were only 5-10 bees in the rim area. 2 of the 3 hives that left the syrup mostly untouched were 'lighter hives' in my estimate.
@Paul: I have no doubt that your bees would take the syrup given the temps. Trex raises a good point: its hard for the bees to dry the syrup for storage. However, don't they also consume some of it now, which would preserve some of the stores longer?
-O