Compost-Based Growing Media Improved Yield of Leafy Lettuce in Pot Culture

Compost-based media were examined for effects on plant growth of leafy lettuce (Lactuca sativa L.) in pot culture. Four types of locally sourced composts were created using different proportions of wood chips from untreated pallets and mixed tropical tree debris, food waste from restaurants, and chicken manure. Compost-based media were prepared by mixing each compost with a commercial peatmoss to create 25, 50, and 100% compost-peatmoss mixtures (by volume). In Trial One, cv. Starfighter had the greatest shoot (leaves/stems) biomass when grown in 100% compost containing wood chips, food waste, and chicken manure. In Trial Two, cvs. Starfighter and New Red Fire were examined. Growing media affected all plant growth parameters including fresh and dry shoots and roots, shoot and root length, and number of leaves. Cultivar affected all except fresh root weight. Interaction effects of growing medium and cultivar type were found for fresh shoot weight, dry root weight, shoot, and root length. Regression analyses indicated increases in amount of compost in growing media increased dry shoot and root weights. Composts containing recyclable organic materials can be an alternative to commercial media in pot culture.

Automated summary

Compost-based media were found to have varying effects on the growth of leafy lettuce, with 100% compost leading to increased shoot biomass. Different cultivars and growing media affected plant growth parameters, indicating that compost containing organic materials can be an alternative to commercial media in pot culture.