The summer is over and the autumn prep continues on the bluebird trail. I don’t just soap the ceilings in early spring to deter wasps; I also soap any new nestboxes fresh out of the workshop and installed in late summer through autumn before winter sets in. Here is why. In my location, we can still have warm days in late October into November. One autumn day few years ago, I found this mud dauber wasp species(see photo below) and some spiders building nests in corners of the nestboxes by the ceiling. This happened after the nesting season was completed and no more birds were using the nestboxes. Unoccupied nestboxes can get re-occupied fast by other species. After all, it’s a “house”. It has a roof. Fresh wood is attractive to insects to overwinter (like the mud dauber wasp does) and for spiders’ cottony webs, an easy stick to untreated wood. My method of soaping comes from my days as a kid remembering how goopy soap bars can get in soap dishes, even with just a little water that collects in the bottom of the dish. So I create a soap (think paste) mixture using gentle Ivory soap. I put two small bars of the Ivory brand bars in a plastic Ziploc container (not a Ziploc bag) that has a screw-top which is leakproof and add a little water. I use a pastry brush to create the perfect thin soap paste to then “paint” on the inside walls and ceilings of nestboxes (I do this in spring for all nestboxes and fall for new nestboxes). This deters insects from adhering their nests to the wood. When I soap, I also soap the outside sections underneath the nestbox floors. This is particularly helpful in the summer. I’ve had carpenter bees try to bore holes on the undersides of the nestboxes. The photos below show my method. I find this way so much easier and less hassle than taking bar of Ivory soap and attempting to rub it on the ceiling with my hand–it’s awkward. It does not cover well and it’s difficult to get in those corners by the ceiling. By the way, I should mention if boxes are soaped in the spring, I need not add another thin soap layer UNLESS it’s problematic and has recurring wasp problems. I’ve found I can paint a thin layer on or around March 1 (maybe earlier in warmer weather), and most nextboxes are good to go through the full nesting season. I don’t have to reapply any soap again (such as between each nesting). The goal is to have as many nestings in a nestbox in a season. Once wasps, hornets, and bees use a nestbox, the birds will not. Some incubating females have been known to abandon a nest with a clutch of eggs. My philosophy is DETER the problems; thus I soap all my nestboxes in the spring–hopefully just one application is needed.
Other for preparing the nestboxes for roosting birds for those cold winter nights, my tasks for the nestboxes will be completed until next February, anticipating yet another nesting season in Southwest Virginia on the Woolwine House Bluebird Trail — now at 30 monitored and maintained nestboxes with the trail expansion recently completed. I might increase it to 33!