“If you want to encourage a diversity of bees, then it’s important to have several slightly different diameters and depths of holes as well,” Bratman explains. That could mean bundling thin cardboard or bamboo tubes together within a wood frame, or otherwise drilling an assortment of holes into a block of wood about two inches deep.
While the main point is to provide insect shelter, incorporating other natural and unnatural materials alike can help maintain visual interest for humans too, although the actual nesting material should be natural.
“I once hosted a lovely ‘make our own bee hotel’ party, and I brought out a bunch of scrap wood, we all had power drills, and we drilled holes and placed them in interesting ways [into frames],” Bratman says. “We experimented with bundles of bamboo, and some people even built in bricks.” Be cautious when using paints and varnishes, as bees could suffer from neurological issues from off-gassing coatings, she warns.
A bee hotel can be large enough to cover the side of your house or small enough to hang from an apartment complex balcony. Note: Most bees can’t fly above 30 to 40 feet, Bratman says, meaning a bee hotel won’t do much if you’re on the 10th floor of an apartment building.
Regardless of your hotel’s maximum occupancy, it’s important to make sure that the space remains hygienic. While building a bee hotel can be a low-effort activity, maintaining it to prevent diseases, parasites and rot requires some work so it doesn’t turn into a hotel from hell.
Clean tubes after bee larvae eggs have hatched, or replace tubes with fresh ones. Compressed air or a pipe cleaner should be sufficient to clean out the holes, according to the Edmonton & Area Land Trust. Wood blocks should also be refreshed every few years, but time any maintenance to when bees have hatched and vacated the hotel.
3. Build a habitat for burrowing bees
Building a bee hotel is one way to boost the native bee population, but since there may be thousands of native bee species in the U.S. alone, not all bees prefer a premade cavity. Some types of bees prefer to nestle in the ground, digging their own burrows in appropriate soils.
Bee hotels are “filling an important gap, but there’s also a need for grasslands and for slightly disturbed soils so that ground nesting bees can also be part of the mix,” Bratman says.
Many ground nesting bees live “basically in the underground equivalent of a studio apartment building complex,” she explained. “They will burrow into the ground, make a little nest, have multiple entrances and exits, and be right near hundreds of other bees doing the same thing.”
Miami University experts suggest not tilling or walking over soil inhabited by ground nesting bees to prevent it from compacting. Providing loose, well-drained, bare areas of soil can help those bees make a home more easily. You’ll also want to allow native ground-cover plants, as opposed to regular lawn plants, to take over your yard. A bloom-filled tapestry lawn may be another option. “There’s a lot to be said for challenging the aesthetic of the perfect grass lawn, which is essentially a food desert for bees and other pollinators, and encouraging clover and violets and the occasional dandelion and taller grasses as part of an architectural statement that a landscape can be more pollinator friendly,” Bratman adds.