Whether to provide sun or shade for bees is a contentious issue. Many—perhaps most—beekeepers believe that more sun is better. In fact, many beekeepers go out of their way to make sure their hives are in full sun the entire day.
However, wild swarms left to their own devices always go for shaded areas. After all, they nest in trees and trees have canopies that shade them. Wild swarms don’t select deep shade, but usually choose a location on the edge of the forest that is shaded at least part of the time.
Why the discrepancy? Why do we put bees in places they don’t prefer?
Do bees benefit from full sun?
I think there are several answers. First of all, a hive in the sun becomes active earlier in the day. Bees become active when they get warm—and they get warmer sooner in a sunny location. We see this activity and assume the bees are “happy,” when in fact they are just warm.
Early morning activity is equated with extra nectar foraging, but on hot summer days collection may slow down as the workforce is needed to cool the brood and the hive. Even if nectar is delivered to the hive, the house bees may refuse to take it if the brood nest is too hot. So although you may gain something early in the day, you may lose it later on.
Hives in the sun also get active earlier in the spring and have the opportunity for early cleansing flights. But there are downsides to this as well. If the hive is artificially warm, the bees make take flight only to die in the cold outside temperatures. If it is warm enough to fly, but forage is not yet available, they can waste a lot of energy looking for something that isn’t there.
Most common doesn’t mean best
Another reason hives are kept in the sun is that commercial beekeepers often have no choice in the matter. They often keep their bees in open fields where there is no protection from the sun whatsoever. The rest of us see these busy hives and assume this is the “correct” way to place hives. And the truth is, these full-sun bees do absolutely fine. The workers cool the brood, cool the hive, and thrive through the most treacherous of summers. So should we care about placement at all?
The decision of where to place a hive is often determined by factors outside of the beekeeper’s control. Bees in pollination service are put near the crop they are to work. But even hobbyists are constrained by neighbors, property set-backs, small lots, buildings, rooftop configurations, or a myriad of other considerations.
Nonetheless, it is instructive to read the comments influential beekeepers have made about the placement of bait hives and colonies.
Sun or shade for bees?
This comment appears under the entry for “bait hives” in The ABC & XYZ of Bee Culture. It says bait hives should be
. . . well-shaded, but highly visible; if the sun hits the bait hive the bees will probably leave if no brood is present.
This comment appears in The Backyard Beekeeper by Kim Flottum:
Place colonies where they’ll have some protection from the late afternoon sun.
Thomas Seeley in Honeybee Democracy says of bait hives:
. . . a good location is about 5 meters off the ground, highly visible but fully shaded, and facing south.
All these comments indicate that bees prefer a home in the shade. So my own recommendation is to give your hives some shade if you can and try to avoid full sun. But if your situation dictates otherwise, don’t worry, just make them comfortable by providing adequate ventilation—such as screened bottom boards and https://www.honeybeesuite.com/how-to-make-a-screened-inner-cover/—and a convenient source of water. Your bees will take care of the rest.