A PRAGMATIC APPROACH TO WETTABILITY AND HYDRATION OF HORTICULTURAL SUBSTRATES

Moisture retention has been a key property in substrate analysis for many years. This work explores the relationship between wettability and hydration using a low cost, practical system. Hydration curves and maximum hydration were used to determine three indexes: HE 1 (initial hydration), HE 3 (a watered-in value) and HE 10 (comparing irrigated vs maximum values). Coir, pine bark and sand at 45% moisture and wetting agent reached maximum values with one hydration. However, both coir and peat captured less than half their max in initial hydration when initial moisture was reduced to 30%. Values obtained with this method numerically de-scribed common behaviors of substrates, moisture content and wetting agents.