Why Mason Bees Are The Unsung Heroes Of The Garden

Bumble bees and honey bees, they get all the glory. While we’ll agree they are both surefire signs that spring has arrived, there is a more inconspicuous bee variety that starts working its magic in the earliest days of spring. We’re talking about the mason bee, the unsung hero of orchards, vegetable gardens, and even your own backyard. According to the Ecological Landscape Alliance, female mason bees find their nests in existing tunnels (whether hallow stems, abandoned mud holes, or even manmade nests), creating a wall in the back of the tunnel with mud she has gathered in her jaws, which is how they came by their name. But there’s still more to know about these mighty pollinators. 

"Mason bees, along with hundreds of other types of native bees and wild pollinators, often go unnoticed in gardens, but if you provide the right environment, they will populate your yard and pollinate your vegetables,” says Dr. Lora Morandin, Ph.D., Associate Director at the Pollinator Partnership, an organization dedicated to the protection and promotion of the health of pollinators. And no one does it with quite such aplomb as the mason bee. 

Here we'll uncover how to identify a mason bee, why they're superior pollinators, and how to encourage them to thrive in your garden. 

How To Identify a Mason Bee

According to the Pollinator Partnership Bee Identification Guide, mason bees range in size from 7mm to 16mm (by comparison, the honey bee typically clocks in from 12mm to 15mm and the bumble bee from 8mm to 21mm). Some mason bees have black bodies covered in light-colored hair and others have a metallic green-blue body with noticeably less hair. Both forms have hair beneath their abdomen that carries pollen from one plant to another. Mason bees will have robust bodies with heads that are as wide as their thorax, unlike the long-faced bumble bee and the honey bee with its heart-shaped face. 

Why Mason Bees Are Beneficial

Mason bees are native in North America and pollinate our wildflowers and many of our early blooming fruits and vegetables such as apples, cherries, blueberries, plums, and strawberries," says Morandin. "They are amazing little pollinators, working in the spring before many other pollinators are active." According to the Ecological Landscape Alliance, 250 to 300 female mason bees can pollinate a full acre of cherries or apples, making them truly extraordinary pollinators. The ELA also points out that most of the 150 varieties found in North America are native. 

How To Support Mason Bees

Mason bees are solitary, meaning every female bee lays eggs and raises her offspring without the help of the colony, but nest in groups above ground in pre-existing holes. These premade tunnels can include beetle burrows in old wood, hallow plant stems, or human-made nesting boxes. If you opt to DIY, Morandin says it's important to make sure the house is properly designed for mason bees and constructed so both the cocoons and the house can be cleaned each year. 

If you’re looking to encourage these top-notch pollinators to make a home in your yard, select your plants wisely. "People can encourage mason bees in their yard by having flowers and trees in their yards that bloom in the early to mid-spring," says Morandin. "Leaving some dead vegetation is great for providing nesting for mason bees—stems of many herbaceous plants and shrubs provide natural nesting for mason bees and other wild tunnel nesting bees."