Water Holding Capacity Testing
The Water Holding Capacity (WHC) of a growing media measures the amount of water that a growing media can hold without causing plant stress. The WHC is largely determined by the amount and type of pore spaces available in the growing media, however the height and shape of the growing container also influences the growing media’s WHC (see Container Media Management; K. Bodman & Dr. K.V. Sharman which can be purchased from NGIQ). EcoHort guidelines recommend a WHC of greater than 40% (see EcoHort Guidelines from NGIQ).