Creating nest sites for ground-nesting bees

When I started learning about pollinator gardening, I had no idea that pollinators are so diverse and interesting. Even though I had been an avid gardener for 20 years, I was shocked by how little I knew about these important visitors. If you want to create your own garden, it’s helpful to learn a bit about them in order to meet their needs.

Native, wild bees live quite differently than the familiar honey bees. Most native bees are solitary; instead of living and working with thousands of others in a hive, they live by themselves and each female creates her own nest in the ground or in cavities.

Most don’t live very long as adults, about 3 to 6 weeks. They emerge from their cocoons, mate, and females lay eggs and provision their nests for the next generation. Their larvae grow, overwinter, and emerge the following year. This Bee Friendly page includes an illustration of a native bee life cycle throughout the year.

Ground nesting sites

For ground-nesting bees, you must have areas of bare ground where bees can dig out nesting tunnels. On the surface, they look like small ant hills. Author Heather Holm illustrates this nest style in her poster Ground-Nesting Native Bees. You don’t need vast expanses with nothing planted, but just avoid using mulch and landscape fabric.

Ground-nesting bee nest entrances look a lot like ant hills. You can watch a video of the mining bee digging this nest in my garden on YouTube
(May 5, 2017).
Here she is taking a break and peeking out of her nest. I’m glad she found a bare spot within my old bark mulch.

I have seen bees go in nest entrances near the base of plants or rocks, maybe using these as landmarks or to hide the entrances. We also see them using bare patches in our back lawn.

Since ground-nesting bees are solitary, or semi-social, you won’t see much activity around a nest entrance. They are gentle and fun to watch. If you do see many insects flying in and out of a ground hole, they may be introduced European Yellow-jacket wasps living there instead. Beware because they can be aggressive. I have never had these wasps nesting in my yard.

Learn more about native bees

The City of Toronto’s Bees of Toronto PDF is a great introduction to native bees in Ontario. For in-depth details about Native Bee Biology, visit the Xerces Society web site.

The best book for learning about and identifying native, solitary bees is by Heather Holm. Bees: An Identification and Native Plant Forage Guide is filled with interesting information and beautiful, close-up photos. It is available at the Ottawa Public Library. You can also listen to interesting interviews with Heather Holm on the EcoBeneficial web site, and the Native Plant Podcast.