Skip to main content

Natural Awakenings Rhode Island


Regenerating Soil Naturally

by Wendy Fachon

Vermicomposting is the process of using worms and micro-organisms to turn food waste into nutrient-rich humus. The industry term for vermicomposting is worm castings. According to the Worm Ladies of Charlestown, castings contain a highly active biological mixture of bacteria, enzymes and remnants of plant matter. They are rich in water-soluble plant nutrients and contain 50 percent more humus than normally found in topsoil.

Castings contain a high concentration of nitrates, phosphorous, magnesium, potassium and minerals such as manganese, copper, zinc, cobalt, borax, iron, carbon and nitrogen—all in natural proportions. The Worm Ladies sell red wiggler worms by the pound, worm castings, indoor and outdoor worm bins, books on worm composting and other accessories. Learn more at

Vermicomposts provide many benefits over chemical fertilizers. The beneficial nutrients found in castings are absorbed easily and immediately by plants, unlike chemical fertilizers and manure. While chemical fertilizers don’t improve soil quality and simply salinate and firm the soil, vermicompost prevents soil firming, improves soil structure and restores microbial life. A study published in the Agricultural Sciences journal showed vermicomposts can promote growth 30 to 40 percent over chemical fertilizers at a price-point 50 to 70 percent below them.

Moreover, chemical fertilizers are often washed away and must be reapplied while vermicompost, due to high levels or organic matter, remains in the soil, giving plants continued access to the supplied nutrients. Modern synthetic chemical agriculture can kill beneficial microorganisms, while vermiculture supports them. Finally, vermiculture returns plant matter, and the carbon it sequesters, back to the soil, retaining biomass and nutrients. This benefits the overall environment.

Earthly is a Providence-based social enterprise that produces high-quality worm castings from food waste collected from local establishments. The company's mission is to improve the way society deals with the 40 percent of all food produced that ultimately goes to waste. While most commercially available worm castings are made using uniform types of feed such as grain or cardboard pulp, Earthly’s red wiggler worms are fed a carefully balanced mix of pre-consumer food waste obtained directly from juicing bars and coffee shops. This ensures an extremely high quality diet for the worms that in turn produces equally high quality castings.

Earthly avoids sealing castings in plastic to prevent the suffocation of the beneficial microbes living inside the vermicompost. The company is constantly working to improve eco-friendly packaging options so that the castings can continue to breathe until the grower is ready to work with them. The fresher the castings are when applied, the better.

Currently, Earthly sells primarily to the cannibis market, however, it also provides vermicompost and consulting to organic gardeners and farmers. Earthly supports the no-till method, recommending the layering of straw over freshly applied vermicompost at the end of each growing season. Earthly co-founder Frank Mastrobouno states, “This process requires a lot of work upfront, however, it will lower garden maintenance required through the following growing season.” Learn more at

Wendy Fachon is a regular contributor to Natural Awakenings.