The objective of this trial was to examine the effects of a novel soil amendment, a type of vermichar produced by Terra Optima, on the growth and health of leafy green and fruiting crops.
Terra Optima Labs Inc. (Terra Optima) has created a circular system on-site at the Western Fair District (London, ON, operated by Western Fair Association), which can divert food wastes from landfills and process it into natural soil amendments, fertilizers, and food, using natural organisms. Terra Optima utilizes composting worms that consume food waste and produce a valuable manure output called castings, which has the potential to be used as a natural soil amendment. Terra Optima has created a novel vermichar product; a blend of worm castings and biochar aimed to stabilize and capture nutrients released from the worm castings, as well as improve the beneficial microbial habitat. Terra Optima currently doesn’t possess the knowledge or have access to controlled environment crop growth to perform reliable growth trials to gain knowledge on their product’s efficacy on plant growth.
The effect of Terra Optima’s vermichar on plant growth was tested at different volumes as a media amendment (0%, 10%, and 20%), in addition to being used as a starter for compost tea. Ocimum basilicum (Basil) and Fragaria x ananassa (strawberry) crops were grown in five treatments containing vermichar and/or compost tea, or neither (‘control’). Results of this trial show that 10% vermichar by volume incorporated into media produced benefits for both crops when fertigated with compost tea. Of all treatments with vermichar, basil was the tallest, most green, and produced the highest overall amount of biomass in the 10% vermichar blend fertigated with compost tea. The height and leaf colour of this treatment was similar to the control, however the 10% vermichar and compost tea treatment surpassed the control in the amount of overall basil produced by weight. In the strawberry crop, the 10% vermichar with compost tea treatment initiated flower production the earliest, produced the highest number of fruit per plant, the most amount of fruit by weight, and had one of the highest total soluble solids recorded (°Brix). The growth of both basil and strawberry in media amended with 10% vermichar, fertigated with compost tea, outperformed the commercially available media fertigated with soluble chemical fertilizers.
Funding: The project is being funded by the Niagara College-led Greenhouse Technology Network (GTN), through the Federal Economic Development Agency for Southern Ontario (FedDev Ontario).