Soil testing Your land is the basis of your income and soil testing remains as critical today as it did a generation ago. Taking good soil tests is paramount to helping your land to be productive. You cannot compensate for low soil fertility by applying more fertiliser in the year of production. Soil fertility and health must be built up over time and such land will always produce higher yield potential. Fertiliser application is always about building or maintaining soil fertility on owned land. But this must be balanced with lime or pH which is still the most important single input. You need soil tests to get this right for either winter or spring crops. There is little point in testing a field where fertiliser was recently applied.