Evaluation of compost as an amendment to commercial mixes used for container-grown golden shrimp plant production

Abstract

Growth of golden shrimp plant (Pachystachys lutea Nees.) transplants was evaluated in media containing 0%, 25%, 50%, 75%, or 100% compost derived from biosolids and yard trimmings. A commercial coir- or peat-based media was amended with compost. As compost composition in the peat or coir-based media increased from 0% to 100%, carbon/nitrogen ratios decreased; and media stability, nitrogen mobilization, pH, and electrical conductivity increased. Bulk density, particle density, air-filled porosity, container capacity, and total porosity increased as more compost was added to either peat- or coir-based media. Plants grown in media with high volumes of compost (75% or 100%) had less leaf area and lower shoot and root dry weight compared to the controls (no compost). Regardless of percentage of compost composition in either peat or coir-based media, all plants were considered marketable after 8 weeks.