Worms produce nutrient-rich compost for our production fields. We have a healthy population of red wigglers in a newly-constructed vermicompost (worm compost) facility. They live in a crank-operated bed, in which the hungry worms remain close to the top to be near the food source, mostly food and crop waste. Red wigglers flourish in dense, highly populated conditions and are voracious eaters. Red wigglers have the ability to consume half of their weight in organic matter each day!
The worms’ processes of digestion produce castings, which contain a diverse array of beneficial microorganisms and nutrients. When we turn the crank on the bed, scrapers go along the bottom of the bed, which is satiated with the castings along with other organic materials present in the system; this makes up the vermicompost (worm compost). They then fall to the ground, readily available for our use. The vermicompost can be applied to potting soils, promoting beneficial organisms, pathogen control, longer nutrient life, and enhanced growth of seedlings. Additionally, it can be made into a liquid extract – a “tea” of sorts – by placing a vermicompost-filled mesh bag into an aerated tank of water. The extract can be sprayed onto the leaves of plants to suppress disease and increase the amount of available nutrients.
Anna Farb, Dickinson ’12, is currently conducting independent research on the effects of vermicompost in potting soils. With a simple mix of equal parts by volume of vermicompost, peat moss, and vermiculite, lettuce and pak choi plants grew relatively well in relation to a commercial organic potting mix. However, she plans to add a small amount of a few organic amendments to the mix in order to increase the amount of nitrogen, phosphorous, and potassium available to the plants. Furthermore, peat extraction causes habitat degradation and greenhouse gas emissions; therefore, coir, a fibrous byproduct of coconut production and an effective substitute for peat in potting soils, will be assessed in order to define the most efficient, economical, and sustainable potting soil mixes. She also hopes to find out if liquid vermicompost extract will impact plant health and productivity if sprayed onto foliage.