Last month Haifa South Africa participated at the Urban Agri Summit 2017. As an expert agronomist I shared the audience with my knowledge on CRF
Controlled release fertilizer (CRF) is the fertilizer of choice for the future, especially for, but not limited to, open field crops. Haifa, the pioneers in the field of Fertigation, are now also pioneering the use of CRF in many crops, even extensive open-field crops such as corn and wheat and all varieties of vegetable and fruit crops.
Fertigation, in short, is the accurate application of nutrients through the irrigation on a continuous basis. Where fertigation is more suited to intensive areas such as green houses, CRF is more suited to the extensive open field agriculture, providing similar accuracy and continuity of nutrient availability during each growth stage.
Multicote Controlled Release fertilizers are produced by coating water-soluble fertilizer granules or prills, such as Urea, Potassium nitrate, MAP, Ammonium sulphate, NPK compounds, etc with a polymer coating: https://www.haifa-group.com/controlled-release-fertilizers-crf
The polymer coating acts as a membrane around each granule controlling the release of the nutrients inside through a process called diffusion. The release begins once the granules are exposed to moisture which enters the granule to dissolve the nutrients inside. As long as the granule is surrounded by moisture the diffusion process will continue, releasing nutrients constantly for the period for which the coating was designed.
The diffusion process is speeded up the warmer the temperature of the soil solution. For this reason it is possible to determine the longevity of release, based on expected temperatures of the soil during the crop's growth cycle.
Using this technology enables a grower to apply a full season's fertilizer as a base dressing, only topping up if needed. Haifa's agronomists are able to recommend mechanical blends of different Multicote components along with conventional granular fertilizers such as Triple Superphosphate, Urea, etc. that have a nutrient release rate that matches the crop's physiological growth stage in the correct NPK ratios at each stage. We call these blends Multicote Agri or Multigro.
Multicote Agri can be used on any crop where fertilization is required to ensure sufficient nutrients are available for optimal crop production. Using Multicote Agri has a whole range of benefits over conventional fertilization methods, such as :
- less applications - often only a single application of NPK required for the whole season;
- reduced management efforts (time) to monitor fertigation systems or trying to determine optimal timing of side dressings which are weather dependant;
- less nutrients applied;
- the limitation of losses through volatization and leaching;
- more environmentally friendly - no high EC's killing off microbial population or leaching into underground water sources;
- fertilization is independant of irrigation allowing irrigation scheduling to be based on crop water requirement only;
- to name just a few.
By applying Multicote Agri at time of planting directly in the expected rootzone we are able to create a "feeding zone" where the roots can settle comfortably and take up the required nutrients immediately as they are released. This means the plant saves energy by not having to go hunting each time for new sources of food. This energy is then better utilized producing optimum yields.
For My presentation: https://bit.ly/2xr5Wa6
CRF product page: https://www.haifa-group.com/controlled-release-fertilizers-crf
Written by Michael Koch, Agronomist for Haifa South Africa.
