Can I replace soil applied granular fertilisers with liquid fertilisers?
As discussed earlier, due to several reasons, the uptake of nutrients by crops from liquid fertilisers are much more efficient than uptake from granular fertilisers. This allows less fertiliser to be used, resulting in considerable savings. As the availability and efficiency of liquid fertilisers improve, it is expected that liquid fertilisers will replace granular fertilisers; although to what extent is not yet known. Long-term trends of liquid fertiliser use in Australia can be expected to follow those set in USA, Canada and Europe. A comparison of nutrient forms used in granular and liquid fertilisers illustrates the efficiencies of liquid fertilisers. Nutrient Granular Liquid Nitrogen Usually made from ammonia (more expensive to granulate) Usually as urea and nitrate (less expensive) Phosphorus Immobile in soil (more needed) Foliar and soil-applied types of P more efficient (less needed) Potassium Less mobile in soil and prone to fixation in some soil types Potassium applied direct
