What’s the secret to enjoying more blooms and greater harvests? Pollination! To increase the pollination of your garden plants, consider getting a backyard bee house for native solitary bees, such as mason bees and leafcutter bees.
Bee houses (or hotels) are similar to bird houses, but instead of attracting birds, they attract native bee species, like mason bees. Unlike honey bees, these solitary bees are extremely docile and up to three times more effective as pollinators. No, you won’t get any honey, but you will enjoy more flowers, thriving plants, and healthier vegetables and fruit in your garden!
Bee houses consist of a wooden, birdhouse-like structure containing native bee nesting materials—typically hollow reeds or cardboard tubes. They are the perfect habitat for solitary, hole-nesting bees, who also happen to be some of the best pollinators around.
Wild Bee Motel from Crown Bees
6 Tips for Managing a Successful Bee Hotel
Here are a some great tips for keeping your native bee house buzzing:
1. Avoid bee houses that are too large
While a bee house that is 4 feet wide and 6 feet tall looks great, draws a lot of attention, and raises awareness of native bees, this size is much too ambitious and will likely become a burden to maintain. Like birdhouses, which ought to be cleaned out at the end of each year, bee houses need to be refreshed annually with new nesting materials. Bee hotel maintenance takes little effort overall, but consider the time that you can devote to managing the bees that move in.
Be sure to choose a bee house size that matches what the surrounding area can provide. For example, a stand of flowering trees and bushes can provide more pollen than a meadow of flowers can, meaning a larger house would be appropriate for the former.
2. Protect nesting materials from wind, rain, and birds
Hole-nesting bees need a place to live that’s dry and safe. The ideal bee house will have a solid outer structure that has a 2–3” overhang, which will protect nesting materials from bad weather. If birds are attacking the nesting holes, use a 1”-wide wire cloth and bubble it around the bee house. Do not install wire cloth flush against the nesting holes, as this will obstruct the bees from entering. Bees need some space for landing and taking off!
This bee hotel provides a number of different nesting materials for inhabitants.
3. Provide nesting holes made of the right materials, in the proper size range
Natural, locally available nesting materials are best. For hole-nesting bees, cardboard tubes and lake reeds in the right size range are readily available online.
Avoid bamboo and plastic straws, as these do not let enough moisture escape, causing problems for developing bees. Nesting holes should be between 4–10 mm in size and should be about six inches long. (Nesting holes that are too shallow will skew the sex range of the next generation’s bees.) Many bamboo shoots are much too large for any North American bee to use.
4. Location and a word about predatory wasps
Orient the bee house to face the morning sun, as hole-nesting bees need the sun’s warmth to give them energy to fly. Placing two bee houses—each facing a slightly different direction—can produce even better results.
Most native bees prefer some afternoon shade, but too much shade could attract hole-nesting wasps. Solitary wasps are generally considered beneficial predators in a garden, as they attack pests like caterpillars, grubs, and aphids. However, they may also prey on the bee pupae in your bee house.
The inside of a bee’s nesting tube. Photo by Crown Bees.
5. Protect developing bee larvae during the winter
Make sure that your bee house is accessible, so that you can easily remove filled nesting materials and store them in a warm, dry place. You’ll want to keep nesting materials in locations that have similar temperatures as the outdoors, like a garden shed or unheated garage. Removing and protecting filled nesting holes in something like a fine mesh bag helps to keep small parasitic wasps from attacking larvae.
Keep an eye on the filled nesting materials, as your bees may be a species (such as leafcutter bees) that produces multiple generations per season.
6. Harvest bee cocoons each spring
After protecting and storing filled nesting materials over the winter, open materials and harvest cocoons in the early spring. If you can, organize and separate cocoons based on appearance and when their nesting holes were capped. With proper care, these cocoons will develop into a new generation of native bee pollinators and residents of your bee house!
To learn about keeping honey bees, see our Beekeeping 101 series.