Water is critical to plant production. Not only are plants composed of over 90% water by weight, but water maintains plant turgor and is involved in virtually every physiological process including photosynthesis and nutrient transport. In containers, water plays a central role in delivering almost all production inputs to plant roots including fertilizers, pesticides, PGR’s and anything else mixed in the growing media or applied to container surfaces.
Some weather factors such as high heat, drought or heavy rains cannot be controlled. One of the most impactful decisions a grower can make to prudently manage water use is to select a high-quality growing media. The physical structure of the media (total porosity, water and air holding capacity) will determine the potential of a mix to hold the correct amount of water and air while providing adequate drainage to optimize plant growth. Once you decide on a growing media with consistent physical properties, it is easier to manage irrigation frequency and leaching fraction within practical limits.
The ideal mix will readily take up applied moisture, saturate quickly, avoid channeling, and drain free water quickly to avoid anaerobic pockets in the root zone. Grower media are made from a variety of raw materials and some of these can present barriers to water penetration, infiltration and free drainage, e.g.:
- sphagnum peat moss is derived from decayed bog plants with waxy cuticles
- poorly aged or composted bark can contain fungal mycelium that can shed water as well
- wood products
A good commercial media will be made with quality components and likely contain a wetting agent applied during blending. If the mix is fresh, water relations in the container can be excellent right after potting. However, one common issue with these wetting agents is that they commonly do not last as they are subject to environmental and microbial breakdown. Since mix can be stored for long periods of time after production at the mix plant, in distributor warehouses or at grower operations, these wetting agents can decay and become less effective. When this happens, mix can become harder to wet, contain dry spots or layers, hold less water and can even be poorly drained. This can cause all sorts of production problems and plant stresses including wilting, overwatering and poor nutrition.
The solution for growing media with poor wet out is to apply a high quality growing media surfactant. H2Pro™ for Greenhouse and Nursery wetting agents is a fairly new product line from ICL Specialty Fertilizers specifically designed for poor wet out, channeling and excess drying of pots. H2Pro is a proprietary blend of wetting agents, penetrating agents, and re-wetting agents that can optimize the water relations in stressed growing media. This unique, long lasting wetting agent can be an excellent tool to increase the efficiency of water/nutrient/chemical use, improve drainage, reduce stress, and conserve resources.
One area where H2Pro really shines is with long term activity. Wetting agents have polar molecules with lipophilic ends that attach to organic components in the growing media and hydrophilic ends that hold plant-available water in the root zone. H2Pro contains wetting agents with a variety of chain lengths. The longer chain lengths take longer to decay, providing extended wetting and rewetting ability through repeated wetting and drying cycles.
H2Pro can be used in a variety of ways
- incorporated in growing media
- as a drench application
- at low rates in the irrigation/fertigation system
- as a misting agent on fresh stuck cuttings
- as a continuous overhead watering application
- to remove sitting water on foliage
- as a drench on containers and baskets prior to shipment
Key features and benefits of H2Pro
- available in liquid and granular formulations to fit a wide range of applications
- low foaming
- liquid is highly compatible in tank mixes
- excellent initial wetting, spreading, better penetration
- stays in solution even at cooler water temperatures
- economical and long-lasting
H2Pro applications can be an excellent way to minimize plant loss in the post-production environment of the big box or garden center where watering may be less than optimal. Here, lost crops equal lost profits. In a recent trial, plants treated with H2Pro maintained turgor for over a week after being watered while untreated plants reached permanent wilting by Day 5 and were not salable. Additionally, when dry pots were watered with 16 fl. oz. of water after this dry down, treated pots held 12 fl. oz. whereas the untreated pots held only 7 fl. oz. H2Pro treatment led to higher survivability of crops subjected to drought stress and better mitigation and recovery of dry growing media.