Organic based soilless media is used extensively in hydroponic production systems. Media may be made from coir, sphagnum peat or composted pinebark or be blends of two or more of these components. Organic media can be difficult to wet up from a dry state and be prone to developing dry patches that do not re-wet properly during normal irrigation/fertigation cycles. Instead of evenly wetting up media, water and nutrients will flow downwards via narrow channels and the area for effective root growth will be reduced.
Uneven wetting of media can have a significant effect on crop health. Plant roots need a consistently moist environment for normal physiological functioning. Media with dry patch issues will support less root growth, hold less available water and require more frequent irrigation.
The physical properties of the media can be improved by using a high quality, biodegradable wetting agent that will eliminate dry patch and allow crop roots to ‘access all areas’ of the media. Good quality wetting agents include both short-chain penetrant and longer-chain residual surfactants that reduce surface tension to significantly improve the lateral movement of water. They are essential to optimise the physical properties of organic media, such as improving moisture distribution, total water holding capacity and air-filled porosity.
This presentation will focus primarily on results obtained using ICL wetting agents, such as H2Coco and Hydraflo in organic growing media. Measured benefits have included:
Crops perform at their peak when root growth is unimpeded. Careful use of high quality surfactants can optimise the physical properties of media and allow roots to access all areas, resulting in more efficient production.