Nest boxes should be cleaned out each year.  You will greatly increase the chance of bluebirds (and other desirable species) nesting in your box if it is cleaned annually; this is why our box design comes with a pivoting door.  To give all cavity nesters time to complete their breeding cycle, it is safe to clean boxes between September-February.

Eleanor Hartmann finds a swallow nest while cleaning

Once you are sure the box is unoccupied, check nest boxes for nesting material (*Note: old nests will typically look “rotted”, contain feces, be mashed down into bottom of box, be full of earwigs or other bugs, etc). Make sure that anyone opening the next box is very cautious when pulling out material…depending on time of year it is cleaned, it may contain overwintering yellow jackets or spiders. Wear gloves for protection. Once you have identified the nest (species that made it), you can remove it and toss it on the ground away from the box (at least 15- feet away; sometimes old nesting material can be a predator attractant).  Sweep out inside of box with hand or a hammer (a car ice scraper comes in handy) to remove remaining insects or nest material.  You can spray the box out with a very mild bleach/water (1:10) solution to kill any bacteria, after cleaning.  Make sure box is securely closed; replace fastener.

Tools and Supplies Needed

  • A tool to open your nest box (depending on the kind of closure it has; hammer for nails, or a multi-tool for screws)
  • a small lightweight step-stool or ladder if necessary to access higher boxes
  • small supply of nails to replace lost/unusable door fasteners
  • gloves
  • ice scraper or hammer for scraping out box
  • dust mask/safety goggles (optional)
  • 1:10 bleach solution (optional, but helpful)

Broken or vulnerable boxes

Please remove or repair, if possible, any boxes that are in peril of falling, or falling apart.  We don’t want to encourage nesting in boxes that may fall down with fragile eggs or nestlings in them.  Also, if your boxes are not yet predator-proofed (PVC sleeve or baffle to discourage raccoons/rats) OR you experienced problems with house sparrows using your boxes, please notify Kathleen and we’ll work through a solution. To contact Kathleen, email