Advantages and limitations
Granular Limes are an agglomeration of very finely ground and/or micronized particles of Calcium or Magnesium Carbonate usually with at least 90% passing a 150 micron sieve. The powder is formed into granules with the addition of a binder which 'cements' the powder for storage, transportation and application, but which dissolves when applied to the soil and in the presence of moisture. Granulating Lime Powders facilitates the application of product which would in its natural form be very difficult to accurately apply.
Manufactured from very fine powders, when Granules are dissolved in the soil solution the alkaline Calcium is quickly and readily taken up to displace excess hydrogen ions (H+) displacing acidity for neutral soil conditions.
Being manufactured from natural quarried calcium carbonates, Granules have a Neutralising Value (NV) similar to natural lime products (50 - 55NV). The manufacture of Granulated Limes does add to product costs and, whilst they offer some advantages over natural bulk limes, as a consequence application rates are generally much lower than their bulk counterparts. Consequently the application of Granulated Limes may be considered as a maintenance application to the top few centimetres in a well managed pH rotation; for a short term rental period; or to alleviate the effects of young crop failure, rather than as a remedial treatment for the whole soil profile.
- High Calcium Carbonate Content (98%).
- Very Fine composition providing High Reactivity (>98%)
- Fast Acting
- Lower application rates
- Convenience Farmers own application using standard fertiliser spreader
- Timing - as/when required
- Ease of application – on bare land or down tramlines
- Spot treatments
- Suitable for difficult or steep ground not suitable for conventional equipment
- Regular granule size/shape for accurate application
- Whilst fast acting the Neutralising Value (50 – 55NV) is similar to natural bulk limes and cannot provide similar long term pH correction throughout the whole soil/rooting zone.
- Higher manufacturing, on-farm costs
- Not suitable for longer term liming rotations 3 – 5 years
- On farm application costs have to be considered in addition to purchase price
- Lower application rates will not work throughout the whole soil rooting zone.