Vermicompost

Vermicompost composition depends on the organic feedstock fed to the worms and on the conditions of the vermicomposting process. Its physical structure is typically finer and more uniform than conventional compost, and its nutrient concentrations, while still low relative to mineral fertilizers, are often somewhat higher in readily available forms.

Nutrient content

Low and variable; depends on feedstock and process

Physical structure

Fine, crumbly, and uniform castings

Microbial content

Typically high and diverse

Nutrient forms

A relatively higher share in readily plant-available forms than raw feedstock

Vermicompost supplies nitrogen, phosphorus, and potassium at low, variable concentrations, along with a diverse microbial community and readily available forms of some nutrients resulting from processing by earthworms.

• Nitrogen, phosphorus, and potassium are present at low concentrations, similar in order of magnitude to other composts
• A relatively higher proportion of some nutrients may be in readily available form
• Contributes beneficial soil microorganisms along with organic matter

Vermicompost is used in vegetable, horticultural, and nursery production, and in home and community gardening, where its fine texture, relatively available nutrients, and biological activity are valued for supporting plant establishment and soil health.

• Fine, uniform texture suits potting mixes, seedling production, and horticultural use
• Contributes a diverse soil microbial community
• Supports soil organic matter and structure similarly to other composts

As with other organic amendments, vermicompost’s nutrient content and release should be considered as part of an overall nutrient budget rather than assumed to match any fixed analysis, since feedstock and processing vary between producers and batches.

Vermicompost generally carries lower risk of rapid nutrient loss than soluble mineral fertilizers, given its organic nutrient forms, but as with other organic amendments, excessive or poorly timed application can still contribute to nutrient runoff or leaching.