top of page

About Mason Bees...

The Orchard Mason Bee is a north American native pollinating bee that is a wonderfully effective pollinator of early spring crops. In fact they are such generalist feeders that they will very effectively pollinate just about any pollen bearing flower that blooms in the early spring.


Studies done in netted orchards show that 250 female orchard mason bees can pollinate apples as effectively as 50,000 honey bees! They will work in cooler weather and more dampness (like the Pacific Northwest habitat) than honeybees and they are absolutely non-aggressive. They seldom wander very far from home and are easy to raise. This makes them the perfect pollinator for home gardens and boutique orchards. Mason bees don't make honey. They make great apples and cherries though!

~ Bring Back the Bees ~

Numerous studies state that pollinating bees are disappearing!   Placing native Orchard Mason bees in your backyard is an EXCELLENT way to combat this decline by 'Bringing Back the Bees'

Mason bees are classified as solitary gregarious bees. This means that they have no real social interaction in the sense that a honeybee population would, but mason bees do like to nest near each other.  What does this mean for you? It means that mason bees don't protect their eggs after they lay them. They actually don't care about you or your children at all so they are the perfect backyard bee. The male has no stinger. The female has one but uses it so seldom that there is a common belief that mason bees can't sting. The females can but rarely do.

The life cycle of these bees is fairly simple. Every spring when the day time temperatures start to get over 50 degrees with some regularity and enough days have passed since the egg was laid the previous spring, the mason bees chew through their protective cocoons, through the mud walls that protect their nesting chambers, and emerge into your garden. The actual date varies across the country from mid February in warm winter areas to late May in colder climates and higher elevations. 


The males emerge first, anywhere from a few days to a few weeks before the females. They spend their time foraging for nectar to build up their strength.  They stay close by the nesting tubes waiting for the females to emerge. These males do a bit of incidental pollinating while feeding but the vast majority of the work will be done later by the female.  As soon as the females emerge from the nesting holes, the males mate with them and then move away. When all of the females have been mated with the males die, and the rest of the season is all females.

Female mason bees spend their days gathering pollen and nectar from flowers within about 100 yards of their nests. They use this pollen/nectar mix to make a lump of bee bread and place it in the back of a found hole. When the proper amount of food has been placed in the chamber the female backs in and lays a single egg into the food mass.  She  works her way down the length of the hole making cell after cell until she has filled the entire tube. Finally an extra thick masonry plug is constructed at the hole opening and the bee flies off looking for another hole. Female eggs are laid toward the back of the hole where it is safe from marauders and male eggs are put toward the front of the holes. In this way a hungry invader is likely to eat males only and leave the females safe. In the mason bee world it is all about protecting the females. Only a few males need to survive to mate the next spring, but every female is important.

By early summer, all the adult females have laid their eggs and they die. The eggs spend the summer developing into new bees, and by fall they are fully mature bees in newly spun cocoons still in the same nesting tubes. They then hibernate all winter and wait for the signs of spring that will have them emerge in your garden. In other words, every year you will see the children of the bees you had the previous year. The colony should continue to grow every year as long as they have holes to lay their eggs into and pollen with which to provision the egg chambers.

~ The Following Calendar Will Assist You in Your Beekeeping ~


  • Shelter should be put out in February filled with clean and refreshed nesting material of your choose

  • Clay can be provided near the housing area and kept it moist as she needs clay to complete each chamber 


End of February, March or April

  • When outside daytime temperatures reach 49-55° F for 3-5 consecutive days without rain, place cocoons near shelter

  • Loose cocoons should be protected from freezing and predators

  • Keep an eye on your housing area to ensure there is enough nesting material to accommodate the population of bees you would like to maintain


April 15th 

  • All bees should have hatched but every season is different.  This approximate date is sometimes earlier and sometimes later depending on Mother Nature. 

  • If any cocoons are not empty carefully cut them open to help the OMB exit.

  • Look inside all cocoons that did not have a bee emerge to prevent the spread of predators


July 1st – July 15th

  • The mason bee work is done for the season and next year’s bees are safely in their tubes. 

  • Carefully take down the shelter out of the hot sun of summer and exposure to birds, predators and other bugs that might want to use the shelter. 

  • Place the shelter and nesting material in a mesh bag or just the nesting material, to keep predators out. 

  • The mesh bag also lets any emerging predators be visible so they can be squished in the bag and prevent them from getting back into the wild

  • Place shelter and nesting material in a cool dry location protected location 


September 15th – 30th

  • The larvae have developed into mature, full-grown mason bee cocoons hibernating over the fall and winter.  

  • If you are using Systems you may start removing the white liners. Keep the removed liners in the mesh bag or other container that will protect the cocoons from predators

  • Sanitize reusable black plugs and water resistant coated cardboard tubes


October 1st – January 31st

  • It is highly recommended that all cocoons be removed from nesting material to wash, sort, sanitize and store until spring

  • At a minimum perform a random sampling of your bees, by extracting cocoons from 10% of 

nesting material. This is to ensure you have a viable population void of predators

  • The Orchard Bee Association has names and photos of what predators to look for when removing cocoons

  •  Store cocoons in the vegetable area of the frig not less than 39°F with a humidity level of  60 to 70%   

  • That is the one year life cycle of a Mason Bee

bottom of page