Which came first - the Red Wiggler, or the cocoon?
Cocoons
Without delving into philosophical rabbit holes, life begins for an individual red wiggler worm inside of a cocoon. These cocoons, when laid, are white and almost transparent, but quickly darken to a yellow color. When the worms are about ready to hatch it will get even darker, appearing like a dark yellow-brown. Just before they hatch, you will be able to see the baby worms inside of them.
Each cocoon is a capsule for 1 to 7, but usually 2 or 3, fertilized worm eggs.
After an average of 21 days, the baby worms will exit the cocoon through the tapered end of the cocoon.
Growth
Baby Red Wigglers are very small, and can be difficult to see. A worm fresh out of the cocoon will be about a fourth the size of this one pictured.
For the next 40-60 days, the worms grow bigger and fatter as they eat. After that time frame, they will become adults and start reproducing!
Adulthood
Sexually mature adult red wigglers are easily identified by their clitellum - the band around the earthworm's body towards their head.
Red Wigglers, and all earthworms, are hermaphrodites! They have both male and female reproductive organs. The clitellum is similar to human ovaries as it stores the unfertilized eggs of the worm.
The male reproductive glands are near the underside of the clitellum, but are more difficult to see.
During sexual reproduction, two worms will line up their reproductive organs to be able to exchange reproductive fluids to each other. Both worms will get 'pregnant' from the encounter.
After the exchange of fluids, each worm will form a mucus layer around the clitellum, that will be sloughed off to form a cocoon.
In laboratory conditions, Eisenia Fetida have been found to be able to produce up to 3 cocoons per worm per week.
The total lifespan of a Red Wiggler has not been thoroughly researched, but is a matter of years rather than months or weeks.
Size
As previously mentioned, Red Wigglers naturally do not grow much bigger than 3 inches or so. The more nutrient dense, wet, and less crowded their environment is, the bigger they will get. A well fed worm can get as heavy as 1 gram!
