Mature breeding worms are easily identified by their clitellum, the swollen band located near the head. That is why some worm farmers call mature red wigglers “banding worms.” Worms are hermaphrodites, meaning each one has female and male organs. However red worms still need to join to breed.
During mating worms slide along each other until their clitellum are aligned. They hold on to each other with bristle like hairs, called setae, located on their underside. While embraced they exchange reproductive seminal fluids which is stored for later use.
During the mating session, which lasts for about 3 hours, the worms secrete mucus rings around themselves. When the worms separate the mucus rings on each worm begins to harden and eventually slides off the worm. But before dropping off all the needed reproductive materials are scooped up into the ring.
When the mucus ring drops off the worm the end seals up, causing it to taper at one end, causing the familiar lemon shape of the cocoon. Over the next 20 days the cocoon darkens and hardens. The hatchlings inside the cocoon grow for a little over three months. Usually three hatchlings emerge from each cocoon.
Red worm hatchlings are not red; they start out looking like small white threats. Then take on the dark red color associated with red worms.
Red worm cocoons have been known to survive for over two years when poor environmental conditions put worm survival in jeopardy and hatching is prevented. When temperature and moisture conditions improve the hatchlings emerge and the reproduction cycle kicks into high gear. Some worm farmers actually withhold food and water to simulate drought conditions and bump up cocoon production. We don’t recommend this for the home composter as it has the potential to kill off too many of your best worms.