For people who've always admired and loved butterflies, creating a butterfly house from a gourd is an ideal way to help these gentle creatures that flutter amongst brightly-colored blooms in the spring and summer. When cold weather hits, many butterflies look for a secure location to hibernate and the gourd butterfly house provides a protected location for them to stay in until spring and warmer weather arrive. One of the keys to creating a butterfly house from a gourd is to size the holes correctly; contrary to what many people think, butterflies are quite agile and can bring their wings together to slip into openings that are quite narrow, which keeps predators from getting them.
Select a quality gourd for your butterfly house. Choose one that has an elongated shape and is at least 12 inches tall in order to allow enough room for the butterflies. Penguin gourds are a good variety to use for butterfly houses because of their elongated shape, according to Fernsink Gourds.
Allow your gourd to dry completely. Set it out in the sun in a location that has a lot of air circulation to promote quicker curing time. This process may take several months, so plan accordingly. The gourd is completely cured when you're able to hear the seeds rattle inside when you shake it.
Soak your dried gourd for 10 to 20 minutes in a dishpan of warm water. Clean the mold off the surface of the gourd with a steel dish scouring pad. Dipping the gourd in a mild bleach solution (one-part bleach to nine-parts water) will help kill any mold spores remaining after your thorough scrubbing, according to Mickey Baskett, author of "Quick and Easy Gourd Crafts."
Cut a cleaning hole in the bottom of your gourd. Use a pencil and a jar with a 2- to 3-inch diameter to mark the hole on your gourd. Use a keyhole saw to cut out the hole carefully. Clean the inside of the gourd with a long-handled spoon to remove all the loose seeds and any hanging pieces of pulp.
Make ventilation and hanging holes in the top of your butterfly house. Use a 1/8-inch drill bit to make four holes around the circumference of the gourd's stem. Locate the holes approximately 1 inch from the edge of the stem.
Cut butterfly entrance holes vertically on one side of your gourd using your keyhole saw or a mini jigsaw. These holes should be approximately ½ inch wide and about 2 inches tall in order to allow the butterflies enough room to enter the house with their wings closed. Stagger the holes in two alternating vertical rows across the front of the gourd.
Treat the gourd with wood preservative to allow it to last longer outside where it's exposed to inclement weather. Put it in the wood preservative for about 16 to 18 minutes and let it hang to dry and air out for three to four days.
Insert hanging wire into two of the four holes on the top of the butterfly house so you can hang it outside. Insert three to five pieces of tree bark in the cleaning hole in the bottom of your gourd for the butterflies. Close off the cleaning hole with a cork that fits the hole securely. Remove the cork and clean the butterfly house out once yearly, replacing the tree bark each time you clean it.