My colonies went absolutely nuts for the white mustard over a period of a couple of weeks mid-July last year. The farmer had planted it to turn into the soil as a green manure. Walking through the field, the sound of the bees was like a jumbo jet engine. As such, it ended up forming a large part of my summer honey (I forget the exact percentage, but, in the CEH analysis, it was the 3rd most prevalent taxa, after bramble and white clover). Experiences ... Well it caused my honey to set bl**dy quickly. I extracted early August, and probably 15 percent was already crystallised in the frames. The honey, when it came off, had a distinct, not unpleasant 'heat' from the mustard, but that soon faded. I jarred it immediately, and it set within a week. That said, it tasted rather lovely... as does all my honey ;-) I'm rather relaxed about what my bees gorge on - it's all part of the fun! This year, for example, I've had my first encounter with dandelion honey. That, incidentally smells rank, tastes amazing, and seems to darken and crystalise quickly. The mustard, as Ian says, is similar to OSR. Indeed, I think it is closely related.
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