Physical Properties of Peat-based Substrates Amended with a Mature Dairy Cow Manure Compost Before and After Plant Cultivation

Abstract

Initial and final physical properties of four substrates based on a sphagnum peat moss:perlite (3:1 v/v) substrate where mature dairy manure compost (DMC) was partially substituted for peat moss at 0, 16, 26, or 33% DMC of total substrate volume (equivalent to DMC to peat moss ratios of 0, 1, 2, or 3 on a dry weight basis, respectively) were evaluated during a 12-week crop of ‘Macumba’ pot chrysanthemum [ Dendranthema × grandiflora (Ramat.) Kitam]. The impact of time on physical properties was similar in all substrates, indicating that DMC was as stable as peat moss. Addition of DMC to substrates increased bulk density (D b ) and lowered total porosity (TP) and air space (AS). Compared to peat moss plus perlite without DMC, container capacity (CC) increased with 16 and 26% DMC and was similar at 33% DMC. Addition of DMC at 33% resulted in a decrease in available water (AW). Plant shoot dry weight was higher in all substrates containing DMC, with the maximum at 26% DMC, compared to peat moss plus perlite without DMC.