Growing Media Water Holding Capacity Testing 9 May 2019 Version Download 587 File Size 0.00 KB File Count 1 Create Date May 9, 2019 Last Updated May 9, 2019 Download Description Knowing the amount of water held within a growing media, referred to as Water Holding Capacity (WHC) of your growing media can help you manage irrigation scheduling more effectively and ensure plants have adequate moisture.