(with expert advice from Cinder Roherty, author of Bee-ing Lily)
Unlike honeybees, mason bees are solitary bees that do not live in colonies. The female mason bee nests in hollow tubes, where she constructs walls of mud to protect her eggs. She will be very picky about the cleanliness of the tubes she nests in, but once she has selected a proper tube, she builds the first mud wall. She constructs these walls by making about 15-25 trips to a nearby source of mud.
After the first wall is built, she will collect pollen from nearby blossoms to create a pollen bed to lay one single egg upon. With pollen bed created and egg laid, she then begins the process all over again, building a mud wall, collecting pollen, laying the egg, building another wall and so on. These walls she constructs are why they are called mason bees (not to be confused with carpenter bees, which actually bore holes in wood surfaces).
Because of her solitary life, the mason bee is not affected by colony collapse disorder or the decline of the honeybee. This makes her one of our most reliable pollinators. A mason bee can pollinate up to 2,000 blossoms a day, though 300 ft. is the furthest she will travel from her nesting tubes for pollen. Mason bees are also not aggressive and rarely sting. When they do sting, it feels like a mosquito bite. You can invite these gentle, hardworking mason bees into your garden by creating a simple mason bee hotel.
Here’s what you will need:
- Regular size drinking straws
- Any container with a back, a soup can works just fine or small wooden box
- A fresh source of mud for her to make walls, this can just be a small bucket of wet topsoil placed near the bee hotel
- A flower bed or fruit trees for her to pollinate, within 300 ft. of the bee hotel
- A secure site facing the morning sun where the bee hotel will not be bumped or blown around, as movement can damage the eggs
Mason bee hotels can be built by just drilling holes in a thick piece of wood or using bamboo tubes, but the picky mason bee seems to prefer the cleanliness of unused drinking straws. Parasites and mites are also more prone to invading her nests if they are made of wood or bamboo. The small mason bees prefer a hole that is 5/16” in diameter, which is the diameter of a regular drinking straw. Large drinking straws cause her extra work building her walls and she can’t fit in smaller drinking straws.
With your container or clean, empty soup can selected, measure its depth and cut your drinking straws so that they are slightly shorter. For example, a 15 oz. can that once held chili beans is about 4 ¼” tall, so I would cut my straws to a length of about 4 1/8” or even just 4” long. This way the straws and mason bee nests will have a little over hang from the can to protect them from rain and flying predators, like birds.
It is up to you if you want to decorate the outside of your can or container with paint, duct tape, etc. Just make sure the inside stays clean and clear. Then, simply fill the can or container with your pre-cut drinking straws and you have a simple mason bee hotel. Place this bee hotel in a secure place facing the morning sun at least 3 feet up from the ground.
The bee hotel container be screwed to posts or walls before inserting the straws. Be sure your little bee girls have a fresh source of mud nearby. As my mother (Cinder Roherty, the crazy bee lady of southern Wisconsin and author of the children’s book Bee-ing Lily) always says during her bee hotel workshops, “If you build it, they really will come.”