From the video: Practical Beekeeping Part 12
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After the first early spring period, the second period of growth and development of bee colonies begins. Wild cherry, pear, plum, apple, and cherry trees have bloomed. The bees are very active on blossoms, dandelions, and other spring flowers.
During the wild cherry bloom, feeders with smaller amounts of thicker syrup are placed for stimulation. The bees bring in pollen and nectar from nature, mix it with the syrup — this significantly helps with the intensive development of spring brood.
A detailed inspection of all bee colonies is carried out. From support colonies, 1–2 frames of mature brood are transferred to production colonies, and empty frames from production colonies are returned to support colonies in place of the removed brood — so the queen can lay in them as soon as possible.
This procedure is repeated every 12–15 days, with rotating the brood box 180 degrees. On the Farrar hive, this fits perfectly into the rhythm of adding brood.
Next comes vertical rotation of brood box supers — the goal is to always give the queen more space for laying and prevent the swarming impulse. All activities in this period — placing pollen traps, horizontal and vertical super rotations, adding foundation and drone combs — reduce the impulse to swarm. Swarming is also influenced by other factors: genetics, queen age, nectar flow, and others.
At the end of the second period, colonies enter the third period of development with about 25,000 individuals (about 2.5 kg in mass). In this period, one bee raises 3.9 larvae — because spring-summer bees have higher quality thanks to their youth. This is the optimal time for setting up production colonies and fighting varroa, approximately 15 to 20 days before the main honey flow.