Bumble bees visit flowers during rainy, cool, or windy weather when other bees stay in the nest, and they are especially good in greenhouse pollination because they do not fly against windows like other bees. In some parts of the world, bumble bees are cultured in artificial nests and used for commercial pollination, but the rearing methods are often proprietary and unpublished. In nature, bumble bee queens start colonies in abandoned rodent nests or similar dry, well-ventilated cavities. In early spring, one can see these bees flying slowly near the ground in search of nest sites. Growers can provide nest sites by leaving undisturbed strips of grass along fence rows, field margins, and other dry, unflooded areas.
Farmers can benefit from growing a succession of flowering plants throughout summer.
This attention to season-long bumble bee nutrition pays dividends with increased queen production and, ultimately, a large, recurring local population of bumble bees. Most solitary bees nest in soil, and some of these bees are very good pollinators. In the Southeast, the most important soil-nesting bees are Southeastern blueberry bees and bees in the genus Peponapis . These solitary bees dig tunnels in soil in which they provision cells with pollen, nectar, and eggs. Southeastern blueberry bees look like small bumble bee workers, but they usually occur earlier in the year than worker bumble bees.