Physical and Chemical Characteristics of Fresh and Aged Spent Mushroom Compost

Abstract

Selected physical and chemical properties of fresh spent mushroom compost were evaluated and compared to the properties of spent mushroom compost which was aged aerobically for 6 weeks. Bulk density, total pore space, total water at saturation, and percentage air space in fresh and aged spent composts were acceptable for plant growth. Both contained very high levels of soluble salts which were readily leachable. Concentrations of metals were acceptable, but concentrations of K, Ca, and Mg could lead to plant nutrient imbalances. Concentrations of NH 4 -N in fresh spent mushroom compost were high.