Gardeners Garden – The Buzz: Mites threaten Mason bees


We gardeners revel in the buzz of our gardens: the bees, hummingbirds, dragonflies, butterflies and moths. It makes a garden come alive.

However, we dont see many honey bees in our garden nowadays because of a mite that is decimating their population as well as causing colony collapse. Fortunately there are about 160 reliable alternatives:  local, native bees that can be easily nurtured.

After lots of research, I decided to encourage the Orchard Mason bee (Osmia lignaria) because it is a gentle, beneficial insect that is also solitary (meaning these bees live and gather food on their own). That meant no hive, no 60 pounds of honey to remove each year (and getting stung doing it), no queen with malaise, no social group of 50,000 bees in a hive situation, none of that.  

Last August, I ordered 300 Mason bee cocoons (and four nesting boxes), through the Internet from a grower. The bees emerged from their cocoons in late March of 2007, and immediately began their fascinating work of buzzing and pollinating in my garden.

The Mason bee is slightly smaller than a honey bee and is a shiny dark blue color. Very industrious in nature, it just goes about its business of pollinating flowers and laying eggs. These bees have never, in any way, posed a problem.

The female Mason bee uses existing (3/8 inches in diameter) holes in wood for a nest. Unlike carpenter bees, Mason bees are never destructive to homes or other wooden structures because they do not excavate nest holes themselves. 

The female Mason bee goes to the end of an existing 4- to 6-inch hole, deposits nectar and pollen and places one egg on top of this food, then seals  up the egg with its future first meal behind a thin wall of mud. This process is moved forward and repeated until the hole is full, then a thick mud plug seals the entrance. Near the nests, you need to have a small, wet muddy area. Line a shallow hole with plastic and keep filled with moist soil or put a bowl of sandy mud out (as I did).

The bees remain in their cocoons throughout the winter, emerging in the spring. There can be some minor mite problems, as well as parasitic wasps and woodpeckers. But there are also easy solutions, too. Look up Orchard Mason bees on the Internet for more details on these beneficial, wild pollinators.

If you want to start your own Mason bee colony next spring, you will want to order your bees now (before house and bee supplies run out), and put the nest boxes up. Sources include or 1.800.275.3618; Dr. Margriet Dogterom (for the bee houses) at in Canada; and Bill Bowlin (for the Mason bees), 3bsales at 1.435.258.2009 in Utah. Enjoy an even bigger buzz in your garden next spring and help out Mother Nature at the same time.

Nancy Burns, owner of Garden Ideas, is president of the Belle Haven Garden Club. contact or 703.329.1899.