Artificially lit crops pollination advice
bumblebee hives high in or above the crops starting from week 40 (+4) until week 10 (-4). Position the colonies to receive direct and early daylight Provide [...] face orientation problems when insufficient daylight occurs (particularly 4 to 10 weeks before or after the shortest day, depending on latitude and en [...] On average, bumblebees are allowed to fly between 10:00 a.m. and 2:00 p.m. (4 weeks before/after the shortest day), with an additional half-hour per week