Water Retention and Transmission Characteristics of Containerized Growing Media Amended with Differential Proportions of Compressed Coir Bricks

The hydraulic characteristics of growing media play an equally important role as do the architectural properties in the production of ornamental potted plants. The reuse of biological agri-wastes, amended with cocopeat and soil, has potential for ameliorating the hydro-physical environment in growing media substrates, affecting air–water relations. A study was undertaken to evaluate the water retention and transmission characteristics of four biological wastes as base media (farmyard manure (FYM), leaf mould (LM), rice husk ash (RHA) and composted sewage sludge (CSS)) amended with different proportions of soil : coir mixture (0 : 75, 25 : 50, 50 : 25, 75 : 0) respectively. These media mixtures were filled in 3.5 l pots. Utilization of coir <50% (per cent of pot volume) as an amendment in FYM and CSS-based media mixtures improved hydraulic characteristics of pot-growing media. The use of RHA amended with soil : coir was not suitable as a growing medium due to higher relative evaporation rate and higher rate of infiltration. Water retention in terms of maximum water-holding capacity and available water increased with coir addition, the increase being enormous with 75% coir. Infiltration rate of water in the media improved with addition of coir (0–50%), showing a steep increase (4.25–8.10 cm min^–1) at highest (75%) proportion of coir. Drainage rate was highest in FYM and LM-based media mixtures.