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

Mari Marutani,Seanne Clemente

doi:10.3390/agronomy11091762

Mari Marutani, Seanne Clemente

Open Access

https://doi.org/10.3390/agronomy11091762

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Abstract

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.

Highlights

Commercial growing media used for container production primarily consists of peatmoss with sand, Perlite, or vermiculite
Lettuce grown in food waste-based composts obtained higher yields and had increased antioxidant activity [8] and soil microbial activity [3] compared to those grown in commercial peatmoss mix
Four different types of compost were created by addition of different amounts of food waste (F) collected from local restaurants and chicken manure (C) that was collected from chicken coops at the University of Guam Agricultural Experiment Station, Yigo Farm, and commercial chicken manure sold locally at garden shops

Summary

Introduction

Commercial growing media used for container production primarily consists of peatmoss with sand, Perlite, or vermiculite. Composts are used as amendments to soil and commercial peat-based media in container culture of vegetables [2,3,4,5,6,7] including lettuce (Lactuca sativa L.). Lettuce grown in food waste-based composts obtained higher yields and had increased antioxidant activity [8] and soil microbial activity [3] compared to those grown in commercial peatmoss mix. Applying composts in pot culture would promote utilization of waste materials as well as recycling locally available resources. The objective of the study was to assess compost-based growing media utilizing food waste from local restaurants and wood chips from used pallets and tree debris as potential substitutes for commercial potting mix to grow leafy lettuce

Objectives

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