I-Cat business development and marketing director Lourens Jansen-van-Rensburg
Advanced hydrogel technology for water and nutrient management is available from I-CAT Agri-Forestry Solutions for a range of applications, from commercial agriculture to landscaping, sod and grass seeding, plant transportation and storage, nurseries, reforestation, soil rehabilitation, and bare-root dipping.
Known as EXLGel, this is a cross-linked, water-insoluble anionic polymer partially neutralised with potassium. Essentially it swells rapidly and forms gel particles when water is added, I-CAT Marketing Director Lourens Jansen van Rensburg explains.
The product is available as a dry, white, solid granulate with different particle sizes for different soil types and excellent absorption power. The latter, in addition to its quick rewetting, even after complete dehydration, and long-term performance characteristics, are determined by the water quality and soil type.
The water-holding capacity of a soil or soil substrate varies from 70 to 120 times its weight. Even higher absorption rates are possible when distilled water is used. Another major advantage is that EXLGel maintains its ability to continuously absorb and release water over several years.
In one particular demonstration, a sandy soil sample retained a litre of water after 40 days without irrigation, whereas the sample treated with EXLGel still retained a litre of water after double that period. This means that the soil moisture potential is sustained for a period twice as long, and at a higher level, translating into reduced drought stress for plants. Therefore the irrigation frequency can be effectively halved.
The soil benefits of EXLGel are increased water-holding capacity, increased filtration rate, decreased water runoff, and reduced soil erosion and leaching of fertiliser. The major plant benefits are improved survival rates, rapid development and uniform growth. Reduced labour, maintenance, and irrigation costs are the main environmental benefits. The product is also safe for humans, and does not pollute the soil or surface and ground water.