Turn Kitchen Scraps into Plant Food

by Rhonda Sherman, NCSU Extension Specialist

Vermicomposting converts kitchen discards into a nutritious soil for plants called vermicompost. When mixed with soil, vermicompost improves its structure, moisture-holding capacity, pH, and drainage. Teeming with beneficial microorganisms and enzymes, vermicompost also contains plant growth hormones and humic acids which can increase rates of germination, growth, flowering and fruiting in crops, usually independent of the availability of nutrients. Numerous studies show that vermicompost can also decrease attacks by plant diseases, parasitic nematodes, and insect pests.

It’s easy and inexpensive to set up a vermicomposting system. All you need are a worm bin, bedding, composting earthworms, and food scraps. You can buy a manufactured worm bin or make one out of wood or a plastic storage container with a lid. Drill holes in the upper sides of the bin for air flow and in the bottom for drainage. Do not drill holes in the lid. Your worm bin can be placed indoors or outside. Popular indoor spots are the kitchen, pantry, mudroom, bathroom, laundry room or basement. Outdoor worm bins should be in a shaded spot that will not get flooded. The worms need temperatures above 55°F and below 85°F, so protect them from cold weather with blankets, hay, insulation or heat tape. Fill the bin half way with moist, fluffy bedding such as shredded paper, brown leaves, or coconut coir. Put in at least one pound of Eisenia fetida earthworms (commonly called red wigglers) that you bought from a worm grower (see http://www.bae.ncsu.edu/topic/vermicomposting/vermiculture/nc.html); just gently empty the earthworms on top of your bedding and they will move downward away from the light. Place a small portion of kitchen scraps in the bin and always cover the food completely with a couple inches of bedding. Don’t ever stir the contents of the worm bin. After three or four months, harvest the vermicompost that has accumulated on the bottom of the worm bin. For instructions on how to do this and more details about setting up and maintaining a worm bin, go to http://worms.ncsu.edu and click on “For Households.”