Study finds food waste compost less effective than potting mix alone

With an estimated 30 to 40 percent of the United States’ food supply ending up as waste, according to the U.S. Food and Drug Administration, food science and horticulture experts teamed up to study if it could lay the foundation for growing the next bunch of crops.

“It’s capturing food waste that would otherwise go to landfill and produce greenhouse gases and cause harm to the environment in some capacity,” said Matt Bertucci, assistant professor of sustainable fruit and vegetable production with the University of Arkansas System Division of Agriculture.

“Instead, we are utilizing it to generate an organic substrate, an organic amendment compost that can then be utilized for propagating seedlings,” he said.

© U of A System Division of Agriculture

Bertucci is part of the department of horticulture within the Division of Agriculture’s research and outreach arms — the Arkansas Agricultural Experiment Station and the Cooperative Extension Service — and the Dale Bumpers College of Agricultural, Food and Life Sciences at the University of Arkansas.

The study, “Assessing Food Waste Compost as a Substrate Amendment for Tomato and Watermelon Seedlings,” was published in HortTechnology last year.

Researchers grew tomato and watermelon seedlings in pure food waste substrate, pure commercial peat moss-based potting mix, and blends of the two with varying ratios to compare seedling germination, growth and nutrient uptake. The pure food waste substrate was made up of food scraps from a commercial partner and wood chips from a tree service company.

The study found that while food waste compost might not be viable as a standalone alternative to commercial potting mix, it could be suitable as part of a substrate mix.

Results showed that mixtures with less than 50 percent food waste compost produced better seedling emergence and growth and had better biomass accumulation than pure food waste, a key indicator of a plant’s health and potential yield.

Still, Bertucci underscored the value of composting food waste, which he said prevents waste from going to landfill and offers a usable byproduct.

“Compost is the sweet spot for sustainability,” he said.

Source: University of Arkansas System