Why do we harvest mason bee cocoons? All creatures have diseases and pests and mason bees are no different. When you harvest cocoons, you save next spring's adult mason bees from walking through a mass of pollen mites or chalkbrood. Clean bees are happy & healthy bees!
Gardeners have asked "Why bother?" as it's natural to have pests. Because we aggregate a lot of bees in one location, it is easier for pests to move from one hole to another. This increases the amount of pests, which accellerates the loss of your bees.
Pre-harvest protective storage. By now, you stored the filled nesting materials in a location that has similar warm temperatures to the outdoor weather, like an unheated garage or garden shed.
Do not put mason bee nesting holes into the fridge yet! Remember that we are mimicking nature's conditions. It's not cold outside yet and the mason bee larvae and pupae depend on the warm summer weather to develop and grow into adult bees. You only place cleaned and harvested mason bee cocoons into the fridge in the fall.
Plan ahead for harvesting cocoons. Mason bees are still developing inside of their cocoons and are not quite ready for harvest. October is the time to start harvesting cocoons and we will have more instructions and tips then.