Vermicompost or worm castings, is created when organic matter passes through a worm's digestive system and becomes a highly potent organic soil amendment. Vermicompost has a high concentration of nitrogen, calcium, magnesium, potash, and other necessary microorganisms for healthy plant growth. The National Sustainable Agriculture Information Service describes vermicompost as "biologically active as well as containing plant hormones which can provide other advantages."
It takes two to three months to make a batch of vermicompost from food scraps, yard trimmings, newspapers or straw, according to University of New Mexico Extension. The last stage of the process is aging the vermicompost. Aging increases the amount of worm castings in the final product.
The Aging Process
Check the vermicompost bin to see that the worms have eaten the majority of the food scraps provided for them. The mixture will have worm castings, small amounts of decomposed matter and partially decomposed bedding materials. The worms convert the remaining material to castings if new food is not available, according to Canadian environmental organization Green Calgary. Stop providing them with new food.
Push the old bedding with worms and partially decomposed materials to one side of the worm bin. Add new bedding and new food to the vacant side of the bin. The new bedding consists of shredded newspapers, non-slick paper, moist peat moss, cut-up yard clippings and food scraps. Keep the bedding moist but not soggy. New food is put in the vacant side of the bin to entice the worms into it and away from the finished vermicompost.
Wait two to three weeks until the majority of worms have migrated to the new bedding area. Remove the vermicompost, including any remaining worms and old bedding, and place in a clean container to continue aging, advises Green Calgary. The remaining worms will eat any partially decomposed bedding and food still in the vermicompost in about three months, according to the organization. The aged vermicompost is now a highly concentrated plant food ready to use in the garden.