1. Sand the gourd with a lightweight sandpaper to clean and smooth it (figure B).2. Once the outside of the gourd is sanded smooth, use a doorknob hole-cutter attachment on your power drill to make a 2" hole on one side (figure C). Use sandpaper to smooth out the hole, then with a long knife or spoon, scrape out the seeds and dried pulp from the inside of the gourd (figure D).
3. To clean and sanitize the gourd, you can use a solution of copper sulfate and water. (Wear gloves and goggles when using copper sulfate and follow all of the instructions on the package.) To treat the gourd, soak it in the copper sulfate for about 15 minutes, then hang it up to dry completely. Be very careful to follow all safety precautions when using copper sulfate!
4. Once the gourd is dry, now comes the fun part. Run a wire hanger through the top to form a hook so it's ready to be painted. To keep the birds cool, it's best to use white for the main part of the gourd (figure E). Painting the gourd is fun for children as long as you use child-safe paints.
5. Once all of the decorations are complete, spray a coat of clear poly on the outside of the house to protect the finish. Then take the gourd outside and find a spot for your new birdhouse. Usually you wouldn't hang a birdhouse near a garden, but a martin house is an exception: martins eat mosquitoes and other bugs by the thousands, so having them near your garden will be a plus.