Humans have used gourds for generations to create an incredible variety of tools, musical instruments, religious objects and storage containers, including birdhouses. The hard-shell birdhouse gourd has a long, narrow stem and a broad, round base that provide an ideal location for housing an array of bird species. Don't plan on creating your birdhouses until spring arrives, since drying gourds is a lengthy process that typically requires about three to six months, according to BirdsandBlooms.com.
Wait for a heavy frost to kill gourd vines. Signs of frost typically include limp, shriveled or darkened leaves. Once the frosted gourd vines have become dry, brown and crispy, you can harvest your gourds.
Select a gourd sized correctly for a birdhouse. According to BirdsandBlooms, look for gourds with a diameter of 8 to 13 inches.
Clip the dead vine approximately 2 inches from the end of your gourd stem using a pair of pruning shears. Handle the stem carefully to minimize chances of bruising or damaging it before the curing process, shifting the vine toward the stem to reduce any pulling on the gourd when you cut.
Carry your gourd carefully to your home and rinse in a bleach solution (1 part bleach to 10 parts water). Dry it out completely with a towel, making sure to remove all water from hard-to-reach areas such as the base of the stem.
Spread a layer of old newspaper across a table or similar surface in a warm, dry area such as your attic or in front of a furnace. Place the gourd carefully on its side on the newspaper and leave it.
Rotate your gourd at least once a week to ensure the entire gourd dries completely. As time passes, you should notice a covering of mold growing on the surface of your gourd; simply wipe the mold off the gourd with a washcloth soaked in a bleach solution (1 part bleach to 10 parts water). Continue this turning and wiping process weekly until your gourd begins to feel significantly lighter.
To see if your gourd has fully dried and cured, pick it up and tap it against a hard surface such as the top of your table. Shake it vigorously; if you can hear seeds rattling around inside the gourd, it is completely cured and you can begin making your gourd birdhouse.