Tips on winter storage and release of Mason Bees
Take $75 off your first purchase of or more when you sign up.
Subscribe now for growing tips, special deals, and updates
We plan to ship mason bees mid-January through the end of February, weather permitting. When you receive your bees they need to be kept cool until you are ready to release them. Keep them in the refrigerator at 36-39° F. It is important to maintain proper humidity for the bees in a frost free refrigerator. Poke several small holes in a plastic bag, put the cardboard box of cocoons inside that bag along with a barely moist paper towel, close the bag, and put it in the refrigerator. In addition to the Mason Bees we also offer the Green Raspberry Bees. These are similiar to the Mason Bees but they fly later in the season and are the best pollinators for berries and other fruits that flower later in the season.
Mason bees will emerge naturally, in response to warming spring temperatures, if you set up the nest box and release box (with cocoons inside) as soon as you receive them. They will survive short periods of exposure to temperatures below zero, but if you expect you will have long periods of sub-freezing weather it will be best to store the bees in the refrigerator until winter has moderated. If you store your bees in the refrigerator you can time the release of your bees to coincide with the bloom time of trees, or groups of trees, in your orchard. If you are just starting a population, you will need to release all of your bees at the same time. Wait to release them until you see flower buds in your orchard beginning to swell, or about 3 weeks before the flowers open.
Place the straws filled with cocoons in the release box you purchased with your straws of bees. The Royal Bee House #T332 also has room for the straws. The bees prefer to emerge from a small dark hole into the rising sun to the east, stepping out onto a small platform they can get their bearings from before they take flight. The hole needs to be above the bottom of the release box, and the same diameter as the straws or tubes in your nest box. Locate the release box near the new nest box the bees will use, so they know where to find it.
You can maximize the pollination potential of your mason bees by releasing them just prior to the bloom of each of your major fruit bloom seasons. Store them in the refrigerator at 36-39° F as soon as you receive them, or right after you clean your established population in the fall (see October Growing Tips for more on cleaning). Keep the bees well cushioned (on a pile of toilet paper, for example) in a container that is porous, so they can breath. Then follow the directions above for keeping them in optimal condition in the refrigerator.
Put a quantity of bees in a release box as each type of fruit is preparing to bloom, or about every 6 weeks. Margriet Dogterom’s book “Pollination with Mason Bees 2ndEdition’ #S427 has instructions on making release boxes from a tin can or cardboard box if you do not have enough release boxes. Be sure to have new, clean places for your bees to deposit their eggs into when they emerge, although it will be a few days before they are ready to use them. Either insert new clean straws in the Calm Bee Nation blocks you used last year, or set out Bee Diverse Stacked Trays you cleaned last fall after removing and storing the bees.