If you are planning to build a wormery, you no doubt know that the ideal worms to use are redworms. They are easy to buy in bulk through a garden supply store or bait store, but you may prefer to search for them yourself in your back yard. In that case, it is important that you can easily identify them. As you can probably imagine, redworms are named for their red skin. The best kind for a wormery compost is the Eisenia Foetida, which is also the smallest variety. Redworms are sometimes called red wigglers, dungworm or red hybrid.
Use a shovel to remove the surface layer of soil in a small area in your garden. An area of about a foot wide and 6 inches deep is enough, as redworms live near the surface of the soil.
Water the area you have opened up generously. Earthworms will start wriggling themselves out of the damp dirt.
Look carefully at the worms that emerge. Redworms are among the smallest, only reaching 2 to 4 inches in length. Mature redworms are dark red and have an enlarged ring around the body closer to the head than the tail.
Put on your rubber gloves and carefully pick up a couple of worms. Besides looking for the enlarged ring around its body, called the clitellum, look for a yellow spot that marks the tip of its tail. If you are looking a reddish colored worm that is between 2 and 4 inches, with a clitellum and a yellow spot on its tail, you have successfully identified a redworm.