Effects of microaerobic fermentation and black soldier fly larvae food scrap processing residues on the growth of corn plants (Zea mays)

Solid residues produced by processing food waste via Microaerobic Fermentation (MF) and by Black Soldier Fly larvae (BSFL) have been proposed as soil fertilizers. Yet, little is known about their effects on plant growth. This study compares the growth of corn plants (Zea mays) in soil amended with MF or BSFL residue, with effects of aerated compost on corn growth over ten weeks. Corn plants grown in soil amended with MF residues were 109% taller and had 14% more leaves than those grown in traditional aerated compost (Cedar Grove). But plants grown in BSFL residues were stunted, growing 39% shorter and having 19% fewer leaves on average. Only height data was statistically significant. Results indicate that MF produced from food scraps is a suitable soil amendment product, but BSFL solid residue from a similar source is phytotoxic when amended, untreated, into soil in a ratio of one part residue to two parts soil. More research on additional post-processing methods for BSFL solid residue is needed.