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I woukd say that if it is yield season, sugar feeding is forbidden. It is allways bad weather and good weathers, but don't rusch to feed sugar.Bees must get its food from nature. That is the rule of game.
When to add super?
When every seam is full of bees. Are you sure how full?
When you add the super/fundations, perhaps it takes one week that bees rise to the super. Yes, it was tool early.
I have cool weathers now.I add supers and boxes but bees do not occupy them.
When I see that new bees are emerging huge amounts and then I put one box up and one down.
So I put the new box under the brood box. Colony expands there and don't start to swarm.
Our day temps are 13-15C. Nature is full of blooming but bees consume all what they forage. They rear new brood and that is the main point.
Autumn rape is blooming but bees do not visit on them if it is 15C and some wind.
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