Growth of Tomato in Biosolids–Woodchip Co‐compost with Varying Proportions of Peat Moss and Perlite Subjected to Two Fertilization Regimes

Abstract

Media were prepared with 0, 16.7, 33.3, 66.7, or 100% biosolids (sewage sludge)–woodchip co‐compost and complementary components of equal volumetric percentages of perlite and sphagnum peat moss, straight perlite, or straight peat moss that received either preplant fertilization or post‐transplant periodic solution fertilization. Shoot dry weight of ‘Beefsteak’ tomato plants (Lycopersicon esculentum Mill.) at 6 weeks after transplanting was not increased by exceeding 33.3% co‐compost, and maximal growth resulted when the complementary components were equal peat moss and perlite or all peat moss. Preplant fertilization or solution fertilization increased shoot dry weight in media containing 16.7 or 33.3% co‐compost irrespective of complementary components. Shoot dry weight in media containing 66.7% co‐compost was increased by preplant fertilization but not by solution fertilization. Using perlite as the complementary medium rather than equal perlite and peat moss or all peat moss decreased total pore space, reduced water retention, and increased air‐filled porosity at container capacity, which was associated with reduced shoot growth in media containing 16.7 or 33.3% co‐compost but greater growth in media containing 66.7% co‐compost.