Wetting agents come in both granular and liquid forms. Granular wetting agents are best for garden beds and pre-lawn installation, as they can be mixed into the soil. Liquid wetting agents can also be used on garden beds and existing lawns.
When applied correctly, both granular and liquid fertilizers are effective tools in maintaining healthy, thriving lawns all year round! Granular fertilizers provide slow-release nutrition that sustains your lawn over a longer period of time, while liquid fertilizers offer quick results with frequent applications.
If you ever run out of wetting agent, a good alternative is a few drops of washing up liquid - does same job.
Wetting agents vary in their effect on water surface tension, water infiltration and water retention.
Application and Safety
Unlike fertilisers that can cause toxicity if applied too frequently or in too large an amount, wetting agents present no such risk. While they won't cause in problems, applying them too frequently is a waste of money – once they have done their job there is nothing more that can be achieved.
The most common wetting agents used are Propylene Glycol USP (PCCA #30-1055) and Glycerin USP (PCCA #30-2865).
BestWet is a liquid non-ionic wetting agent that has been developed for use on amenity grass, golf greens and tees. It is designed to help prevent the occurrence of Localised Dry Patch (LDP) which prevents healthy grass growth.
There are four main types of wetting agents: anionic, cationic, amphoteric, and nonionic. Anionic, cationic, and amphoteric wetting agents ionize when mixed with water.
Allowing soil particles to hold onto water longer can reduce how often and how deeply you need to irrigate. Soil wetting agents can also help channel nutrients into the root zone for improved turf health.
All wetting agents are surfactants, but not all surfactants are wetting agents. Wetting agents are a class of surfactants that lower the interfacial tension of a liquid. An example is water. Water has a high interfacial tension, so a drop of water tends to “bead” on a hydrophobic surface, such as plastic.
Application of wetting agent should be carried out 2-3 times per watering season. A sound strategy is to get your 1st application down early in the watering season (late Oct) long before the Winter moisture is gone from your soil profile.
Can you use granular and liquid fertilizers at the same time? Yes. While you apply granular and liquid fertilizers in different ways, one common way to use these fertilizers together is to apply a slow-release, granular fertilizer as a top dressing at the beginning of the growing season.
Heavy Rain Immediately After Fertilization: Heavy rain, on the other hand, can wash away the fertilizer, preventing your grass from benefiting from the nutrients. In some cases, the fertilizer may disperse unevenly across your lawn, leading to irregular growth or even scorching.
In addition to being less messy, liquid pre-emergents provide better coverage than granular products. Application droplets are smaller than even the smallest granules, so they disperse more evenly over the turf. There's also less room for error when it comes to the physics of applying the product.
( a ) complete wetting, ( b ) incomplete wetting and ( c ) nonwetting. The focus here is on the two-dimensional spreading and diffusive behavior of adsorbates a sub-saturation pressures.
You can buy a wetting agent for hydrophobic soil at most garden centres or make one at home using agar (powdered kelp). It's also possible to use diluted dishwashing liquid or dishwater/laundry water as a soil wetter because the surfactants in the detergent break surface tension in water like wetting agents do.
Jerry Coleby-Williams from Gardening Australia suggests making your own wetting agent from agar agar which is a seaweed product. Buy powdered kelp from a health food shop and slowly incorporate boiling water until you have a thick paste. Add 250ml of this paste to 4.5 litres of water and water this onto beds.*
How long does the wetting agent treatment last? Granular wetting agent treatment can last for up to five months in domestic lawns providing it is applied in the spring when conditions are wet or when it is thoroughly watered in.
You can make your own wetting agent using the same soap you use on your sponge, your hands and dishes.
A perfect wetting liquid forms a contact angle of zero on the solid surface.
High surface energy materials tend to be more wettable. Metals and glass typically have high surface energy, while plastics and other non-polar materials have low surface energy. Surface treatment, like the plasma treatment of a polymer, is often used to increase the surface free energy and thus improve wettability.
If there is any oil or oily compounds on the free surface of the water, then surface tension will be reduced. If you mix something to the water, then the surface tension will be changed. If you electrify the water then surface tension will be reduced.
The key difference between wetting agent and surfactant is that wetting agents can reduce the surface tension, allowing the liquid to spread drops to a surface, whereas surfactants can lower the surface tension between two substances. Wetting agents are a type of surfactants.