Physical Properties of a Processed Dairy Manure Product Used as a Greenhouse Root Substrate Component

The branded product Nature’s Natural (NN) is a double composted diary manure-based product designed to serve similar functions in greenhouse root substrates as sphagnum peat (peat). When physical properties of NN were determined and compared with peat, the total pore space of the peat was 86% (by vol.) while the total pore space of NN was 87%. Air-filled pore space for peat and NN was 12.9% and 12.3%, respectively. Water-holding capacity was 73% and 75% for peat and NN, respectively. Bulk density was 0.09 and 0.10 g^.cm^-3 cm for peat and NN, respectively. Root substrates containing NN generally had similar physical properties as the respective peat-based control root substrate. Physical properties of all NN-containing root substrates were within commonly recommended ranges. The NN lost water at a lower rate than peat and root substrates containing NN lost water at a lower rate than the peat control root substrate. The NN required more days to dry to the 50% (by vol.) moisture level and the complete drying level than peat. Root substrates containing NN required more days to dry to the 50% moisture level and the complete drying level than the peat control root substrates.