Osmia lignaria (blue orchard bee)
Natural Mason Bee Nest Habitat and Bee Hotels
The "Other" Bees - A Beekeeping Alternative
When we think of beekeeping, we think about honeybees. Honeybees are important pollinators and a growing industry exists around providing honeybees for agricultural pollination. It’s also a rapidly growing hobby that benefits the environment and rewards us with a harvest of delicious local honey. But we tend to forget that honeybees are not native. Maintaining healthy hives requires effort and expense. And honeybees sting – painful for everyone and dangerous for those allergic to their venom. If you want to add pollinators to your garden but don’t want to keep honeybees (and don’t mind not getting any honey), consider keeping mason bees.
Mason bees are solitary. There is no hive with tens of thousands of bees and they don’t make beeswax or honey. From March through May, each female lays her eggs in nest tubes (usually holes in trees or walls) that she has provisioned with nectar and pollen. The eggs hatch in two days and the nectar and pollen is consumed in about 10 days. The larva spins a cocoon and pupates. By fall, they look like adults but stay in the cocoon until it’s time to emerge in spring. The name “mason bee” comes from the way the female uses mud to construct walls between each larva and seal off the end of the tube.
Mason bees are gentle enough to be handled and only sting if trapped or squeezed. They are more efficient pollinators than honeybees. A single mason bee’s erratic flight can touch 20,000 flowers in a day – enough pollination for 12 lbs. of cherries – a task that would take 60 honeybees meticulously moving from flower to adjacent flower! This also has the benefit of increasing cross pollination. Mason bees gather dry pollen on hairs on their abdomen where much of it falls off to pollinate the next flower. Honeybees hold it securely on their sticky legs – better for getting it to the hive but not as efficient for pollination. Best of all, while honeybees might forage miles from the hive – often bypassing blossoms in their path – mason bees stay within a few hundred feet of where they were hatched, keeping them in your garden!
Mason bees lay their eggs in existing tunnels like those left by wood-boring beetles or the hollow stems of pithy plants. So, if you want to attract these native pollinators, leave part of your property a bit wild. Natural tunnels are best but you can make holes yourself in a dead tree or block of untreated wood or purchase a bee hotel.
Mason bee hotels are commercially available in a wide variety of styles from rustic to magnificent. Or you can easily make your own. They should be mounted between 3 and 6 feet high on a post, fence, or side of a building (not a tree), facing morning sun if possible and not right next to bird feeders. If you build it, they will come. The cocoons can be left outdoors in the hotel to complete their life cycle. But to improve your chances of success, select a hotel that can be taken apart, so you can harvest the cocoons and bring them inside in June. Harvested cocoons must be put into a refrigerator in November and left there until it’s time to put them back out as the weather warms in spring.
Natural habitat is always best. But, if that isn't possible, installing bee hotels is a good way to support native bees. But bringing many solitary bees so close together can spread disease. We recommend installing several small bee hotels around your property rather than one large one to keep the bees healthy.