HerbDoc just loves her mason bees:
I’ve always wanted to keep bees and even went so far as to take the beekeeping course two years ago. Unfortunately my husband is highly allergic to beestings, and I was never able to go very far in my quest. Recently I decided to try to attract the Orchard Mason Bee (Osmia lignaria) instead.
These tiny blue black bees are very gentle and are termed “nonsocial” because they don’t live in hives. Although many may be present in the same location, they don’t share nests or help to provide for or protect each other’s young. In nature they nest in hollow stems, insect holes and woodpecker drillings. Luckily for gardeners, they will also nest in holes drilled in untreated wooden blocks. Holes should be 5/16” in diameter and 4-8 inches deep. Smaller or shallower holes encourage a higher production of male bees which reduces the reproductive potential of the overall population.
A female mason bee forms a small ball of pollen and nectar in the back of the nesting tube and lays an egg in the ball. She then collects mud, makes a cell partition, and repeats the process until she reaches the opening of the tube. The entire tube is then capped with a mud plug. These overwinter with the males emerging first right around the time the redbud blooms. Females emerge, mate and begin the process of finding new nests.
Many pre-made mason bee “homes” are available from gardening supply companies. These range in price from around $16 to more than $60. I ordered the bamboo house from Gardeners Supply. Suggested siting is against a tree or a wall where the home will receive morning sun. It should also be within 100 yards of the garden to be pollinated.
It is said that these little bees visit as many as 1000 blooms per day – that’s 20 times more than a honeybee! Since they don’t produce honey and are non aggressive, they seem to be the perfect choice for my garden.