How to Keep a Moth Cocoon

Keep your cocoon in an aquarium or in a wide-mouthed, one-gallon jar. Some caterpillars make their cocoons underground while others make them above ground. If you're not sure which type of moth species you have, provide 2 inches of moist soil or sand and position small twigs or sticks against the side of the jar. The caterpillar will form its cocoon in the soil or it will hang it from a twig.

Hang a moistened paper towel in the jar. Tape it at the top of the jar so it hangs all the way to the bottom. The moist paper keeps the humidity in the jar high, which is essential to have a healthy cocoon.

Check the location of the hanging cocoon and carefully move it if needed. Create plenty of space around the cocoon so the moth can fully expand its wings upon emerging without touching the ground. If it cannot do this, its wings may not fully form and it may not be able to fly.

Place cheesecloth over the opening of the jar and secure it with a rubber band. Cheesecloth allows proper ventilation. Avoid using a lid with holes punched into it because this is inadequate ventilation and the sharp edges may harm the caterpillar.

Fill a spray bottle with room temperature water and mist the cocoon every other day to keep it moist. Aim for a water temperature that ranges between 68 to 72 degrees Fahrenheit. There is no need to provide food for cocoons.

Wait two to three weeks for your moth to emerge from its cocoon. Your moth will most likely sit on the moist paper towel to allow its wings to dry. Moths feed on their body fat so there is no need to provide food for them.