Vermicompost is to regular dirt as a gourmet meal is to a few crusts of bread. Plants of course can grow in dirt, but an admixture of vermicompost, which is composed of worm castings or manure, optimizes the soil and nourishes greenery to grow its best. From golf courses to home gardens, turf growers to nurseries, vineyards to greenhouses, vermicompost makes an impact in creating lusher grass, plumper vegetables and healthier flowering plants. (See References 1, page 382)
As does regular compost, worm compost adds benefits to regular yard dirt or agricultural soil. Both regular and worm compost increase the ability of dirt to retain moisture and hold nutrients and improve the soil structure; vermicompost especially boosts the levels of microbial activity, notes researcher Glenn Munroe in "Manual of On-Farm Vermicomposting and Vermiculture." Vermicompost also contains nutrients, such as nitrogen, that stimulate plant growth. (See References 2, page 30)
Scientists are working to quantify the extent to which vermicompost improves crop yields compared to dirt. A test of vermicompost applied to rows of grapevines increased pinot noir yields by 35 to 55 percent, according to "Vermiculture Technology" and worked best applied under a straw mulch (see References 1, page 132). Market yields of peppers were significantly greater for soils that receive both vermicompost treatment and inorganic fertilizer than solely inorganic fertilizers (see References 1, page 135).
If you want better results in your garden or lawn, be sure to add the right amount of vermicompost to your existing dirt. You don't need to completely replace your dirt with vermicompost; in fact, too much vermicompost does not benefit plant growth. The maximum benefit of vermicompost occurs at a ratio of 10 to 40 percent of dirt or potting soil used as a growing medium for seedlings, Munroe states (see References 2, page 31). Similarly, a test of tomatoes in Mexico published in 2007 in "Bioresource Technology" combined vermicompost and soil in proportions of up to 50 percent. Yields of tomatoes as measured 100 days after transplanting, were greatest at a ratio of 1-to-1, 1-to-2 or 1-to-3 of vermicompost-to-soil --- in other words, when vermicompost comprised one-quarter to one-half of the soil. (See References 3)
Dirt can contain certain plant pathogens, such as wilts, blights and root diseases, that attack the root systems of plants. Scientists at Cornell University in the Departments of Plant Pathology and Plant-Microbe Biology and Horticulture, and at the Ohio State Soil Ecology Laboratory, are conducting research that indicates vermicompost actually suppresses these plant pathogens. (See References 1 and 4) Vermicompost may operate by mechanisms including destruction of the pathogen, prevention of its germination, competition for nutrients or competition for infection sites, writes Ohio State soil ecologist Clive Edwards in "Vermiculture Technology" (see References 1, page 204). Vermicompost contains actinobacteria, a type of soil bacteria that has the potential to suppress fungal pathogens, Edwards notes (see References 1, page 130).
- "Vermiculture Technology"; Clive Edwards, et al.; 2010
- Organic Agriculture Centre of Canada; Manual of On-Farm Vermicomposting and Vermiculture; Glenn Munroe
- "Bioresource Technology"; Vermicompost as a Soil Supplement to Improve Growth, Yield and Fruit Quality of Tomato (Lycopersicum esculentum); Federico A. Gutiérrez-Miceli, et al.; November 2007
- Cornell University; Vermicompost: A Living Soil Amendment; 2010
Rogue Parrish is a writer and editor with Demand Media Studios.
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