Since I'm seeing flowers all over out there, including tomatoes and eggplants starting up, I took the mason bee cocoons out if the fridge, put them in the front of the house I made, and installed the house. I also sprayed some mason bee attractant on the house - hopefully, this will keep them here, and maybe attract more from around here.
Mason bee house hung up, with the cocoons slowly opening up. by pepperhead212, on Flickr
I collected some heavy clay soil, and put it in a container, with some drainage holes, and with something to prop it open, so the bees could get to it, then sprayed it with some more of that attractant.
Container of clay, for the mason bees. by pepperhead212, on Flickr
Clay container, propped opened so that the bees can access it. by pepperhead212, on Flickr