Compost Trials

How can we use household waste to help amend field soils? By composting them, blending them with other soil amendments and incorporating them into cropland, that’s how. Or so we hope! 

Work that GRO is doing, in conjunction with AltRoot (local composter of post-consumer organic wastes), Dr. Derek Mackenzie (University of Alberta), his summer staff, and a local producer, will attempt to show if the addition of composted soil amendments increases yields, preserves moisture, and reduces the net emission of greenhouse gases in crop production. 

Started last year, with funding from RDAR, the project had plots near Westlock, Camrose, and Wetaskiwin. The trial plots had compost applied alone, and in various combinations with wood ash, biochar (a product of the incomplete pyrolysis of wood products), gypsum from recycled drywall, and synthetic fertilizer. Control plots with no amendments, and with synthetic fertilizer, were planted to provide comparisons. While the greenhouse gas emission results are still being analyzed, it was found that compost and compost blends did not prove to have equivalent yields to synthetic fertilizer applications. This led the researchers to question if there may be more time required to have compost replace synthetic fertilizers in the field, resulting in further trials. (For results of last year’s trials see the 2022 GRO Annual Report – beginning on page 88). 

In 2023, a continuation of this project is being conducted at the original site in Westlock, and an adapted version at the University’s historic Breton Plots. Compost and compost blends were again applied alongside synthetic fertilizer to get more information on comparative greenhouse gas emissions, soil conditions, and crop yields. Both sites had the various treatments applied mid-May, using the new compost applicator GRO has recently acquired. 

We all look forward to the results of this year’s work to help determine how to incorporate compost and its blends into annual cropping systems in north central Alberta, while minimizing greenhouse gas emissions in cropping systems and reducing wastes going into landfills. 

This year’s results will be available to members in the fall and on our website later this winter.