Some aspects of the soil nutrient profile, or soil fertility, can be manipulated easily and effectively (e.g. phosphorus levels), while other aspects are more difficult to change and are better managed by working to the conditions (e.g. salinity).
The only way to determine the soil nutrient profile is to undertake a soil test. This will reveal important attributes of soil fertility that may influence pasture species selection and fertiliser requirements.
Soil tests can be organised through local rural merchandise suppliers or rural consultants. You can also take samples yourself and send these away for laboratory analysis. The way the soil is collected for analysis is important, with multiple samples required to make up a representative sample.
Soil tests vary in complexity depending on producer requirements. When considering establishing a pasture, the key aspects usually tested are pH, level of salt, available phosphorus, available sulphur and exchangeable cations (calcium, magnesium, sodium and potassium).
The results from soil testing must be considered within the context of the local farm environment. It is advisable to have the results interpreted by a local FertCare accredited agronomist or consultant.
A key outcome of soil analysis and interpretation is a fertiliser recommendation. Soil analysis prior to fertiliser application provides a guide to ensure the correct fertiliser application for the conditions. This gives the pasture the best chance of successful establishment and underpins the pasture improvement investment.
Undertaking soil analysis prior to sowing identifies any soil fertility issues that may hinder pasture establishment. The results can also provide a basis for ongoing pasture management and fertiliser strategies to maintain pasture condition and maximise longevity, without the need for regular soil testing.
Other issues that should be considered when developing a fertiliser program for improved pastures are:
- choosing the right kind of fertiliser for the situation and conditions
- planning the timing of the application
- utilising additional production generated through the application
- ongoing monitoring of soil fertility.