Mason Bees: Nature’s Spring Pollinator

A female mason bee feeding on a clover

Mason Bees: Nature’s Spring Pollinator

Of the 4,000 bee species native to North America, mason bees are among the easiest to raise, while also being gentle and amazing pollinators. Mason bees nest in pre-made holes and hole-nesting bees represent about 25% of the world’s bee species. We can increase mason bee populations by raising them in our backyards and gardens, which is a great way to supplement the stressed honeybee, sustain our future food supply, and provide nesting sites for other native bees, too.

The blue orchard mason bee (Osmia lignaria) is a very productive pollinator for spring flowering fruit and nut trees and spring berry plants. A female mason bee carries pollen mainly on the underside of her hairy abdomen and scrapes the pollen off within her nesting hole. She carries the pollen dry on her belly and it falls off easily as she moves among flowers. Mason bees are generalists that love to visit a variety of flowers.

Dry, loose pollen carried on the large surface of the mason bee’s belly results in significantly more pollinated flowers. Honeybees, on the other hand, wet the pollen and stick it to their hind legs to transport to the hive. Mason bees are an awesome cross-pollinator because they busily flit back and forth between branches and trees, instead of focusing on stripping pollen and nectar from one location.

Mason Bees are Gentle Bees

Mason bees are solitary bees that do not live in a social hive. In fact, 90% (or more!) of the world’s 21,000 bee species live a solitary lifestyle. Every female solitary bee is fertile and she has all the responsibility of building her nest, gathering nectar and pollen, and laying eggs. Solitary bees are gentle because they are too busy to be aggressive and you can watch them without fear. The venom of a mason bee is also very mild and they only sting as a last resort. Mason bees are the perfect alternative for those who are allergic to honeybees.

Mason Bees Save Time and Money

Raising mason bees is easy because they nest in pre-made holes and they hibernate over the winter in small, waterproof cocoons. Nesting materials, housing, and bees are quite affordable, and products are available in a variety of price ranges. Handling mason bee cocoons is simple and there is no need for protective gear or expensive equipment.

In terms of time, plan about 15 minutes to select a location and set up your house. You will end up spending more time watching the bees than taking care of them. Time flies as you watch them laying eggs for next season’s bees!

A female mason bee adds the finishing touches to the end of her nesting hole

When your mason bees are done flying, bring the nesting material inside to protect your developing bees from pests, which takes about 10 minutes. In the fall, allow about 30 minutes to harvest the cocoons and store them for the winter. In just 1 to 2 hours a year of your time, you’ll get a robust garden yield and amazing garden companions.

A bonus is that each year you should typically double or even triple your bee cocoons. Crown Bees, located in Woodinville, Washington, would love to receive your excess bee cocoons in the fall, and trade you nesting material for next season. Your bees will be re-homed to other gardeners and eventually with growers and farmers. They have a BeeBuyBack program you can opt to trade in cocoons for more nesting materials, for a store credit, or for cash.

Mason Bees: Ready Your Garden

Anyone, anywhere can grow flowers and provide sanctuary for native bees. Plants native to your area are the best flowers for bees and native plants are 4 times more attractive to bees. Bees need a variety of flowers that bloom throughout the bee’s season of activity and bees use certain flowers as natural remedies. Lawn chemicals can harm bees and they can also deter bees since bees rely heavily on their sense of smell. Mason bees use moist clayey mud to divide and protect each egg chamber. While mason bees are actively flying, use a shovel to expose a patch of soil. If your soil is too sandy, you will need to provide the bees with a clay mud mixture. The mason bees will not be able to nest in your yard if clayey mud is not available.

Product Recommendations for Raising Healthy Mason Bees

Mason bees need a bee house that keeps their nesting materials dry and protected. The best nesting materials are designed to be opened easily and safely for cocoon harvest in the late fall. Harvesting cocoons is the only way to ensure mason bee health, otherwise diseases like chalkbrood and pests like pollen mites and parasitic wasps can infect and overtake nesting materials. Mason bees prefer natural lake reeds because the lake reeds, just like the bees, vary in size slightly. Lake reeds are also the best protection against the attack of parasitic wasps. Drilled blocks of wood and bamboo tubes are cheap and easy to find, but they can’t be opened, cleaned, or inspected.

A fine mesh bag keeps parasitic wasps from attacking developing bee larvae

In the Osmia genus of bees there are about 350 species and the blue orchard mason bee is just one of the many kinds of mason bees. Each mason bee species needs a nesting hole that is just the right size for them. Blue orchard mason bee cocoons are waterproof and can be stored in your fridge over winter.

Tips for Setting up a Bee House

Install your mason bee house up off the ground, high enough for you to look into easily. The bee house should face the morning sun to warm the bees and give them the energy they need to fly. Do not install the bee house near bird houses and if needed, attach bird wire with one inch openings at the front of the house. Do not attach the bird wire flush with the front of the bee house, instead leave 2-3 inches of space so that bees have the room they need for landing and take-off. Loose nesting materials, like lake reeds and cardboard tubes should be placed in a haphazard manner. Female mason bees memorize their nesting hole by using sight markers and a slightly messy look can help them find their tube faster.

Raising mason bee cocoons is easy, fun, and brings us closer to nature

Raising Mason Bees Can Help All Bees Thrive

The plight of the honeybee gets all the attention but the needs of our wild native bees is actually more pressing. In 2016, the UN announced a worldwide study with the dire news that nearly 40% of our insect pollinators are facing extinction. Raising native mason bees helps us understand and think like a bee and we learn to see our yards and gardens a little differently. Many solitary bees do not fly far from home and mason bees only venture about 300ft (100m) from their nesting house. Mason bee houses provide much-needed habitat for other hole-nesting wild bees as well. You never know what unique and rare native bee you will find and support when you raise mason bees.

Content courtesy of Crown Bees