The last thing I like to do is to wash the birdhouse gourd with a mix of 1 part bleach to 10 parts water. I use a steel wool pad to do this, so that any remaining residue comes off with it. The bleach disinfects the outer gourd and slightly lightens any imperfections on the gourd. It won't make the spots disappear. For perfection, you'll need a fake plastic gourd. The imperfections are what make each birdhouse unique.
