Scientific research in the United States, Scandinavia and Australia clearly demonstrates that fine particle lime (lime flour), has a far greater effectiveness in raising soil pH than coarse particle limes. Some 250kg/ha of lime flour is as effective as 2.5 tons of coarse lime.
Those who denounce the effectiveness of lime flour base their opinions on outdated scientific tests that incorrectly assumed lime particles of less than a quarter of a millimetres were 100 per cent available. It is a proven fallacy that the coarse particles in Ag-lime slow release over a few years.
It’s important to understand that it’s not the ‘tons per ha’ that raises pH, it’s the available ‘surface area of calcium carbonate’ that counts. A 2mm chip of Ag-lime has a surface area of 24 square mm, if that 2mm chip is reduced to 20 micron lime flour, the calcium carbonate surface area increases to an astonishing 2450 square mm.
- When plants remove alkaline nutrients from the soil they leave acidic hydrogen. Rule of thumb shows soil pH will drop approximately 0.1 pa if no lime is applied.
- When the carbonate in the lime raises pH, the lime has worked.
- After liming, soil becomes acidic again but not because the lime has ‘run out’, it’s just what happens when plants grow.
- Because the lasting time is the same, it makes sense to raise soil pH by 0.2 over a few weeks, using 250kg/ha of PFP lime, instead of over 18 months using 2.5 tons of Ag-lime. 250kg/ha of PFP lime will give fast and long-lasting results.
APPLICATION RATES
- First decide your soil pH target. We believe a pH between 6.0 and 6.3 is an optimum level. In this range, nutrients and trace elements are at their most available and above pH 6.0 soil microbial life flourishes.
- To maintain your existing pH levels, apply 100kg/ha PFP lime.
- To raise pH levels we recommend applying 250kg/ha of PFP lime.
Up until now applying lime flour, has usually been difficult, expensive and involved specialised equipment. PFP Fertiliser’s Prilled Lime products provide an easy, convenient and economical way to apply fine particle Lime using any conventional spreading method.
Phone Sandra on (06) 8585235 for an information and sample pack.