Boost spring pastures with effective fertilisation

Applying the right nutrients to planted pastures that are tailored to the specific plant species and local environmental conditions, can significantly boost both yield and quality. However, given the high cost of fertilisers, they must be used efficiently to ensure pastures are optimally utilised by livestock. Renier Bothma, a soil scientist at Kynoch Fertilizers, explains that rainfall is a key factor in pasture production under dryland conditions. The more it rains, the greater the pasture growth and the higher the nutrient demand for maintaining optimal yield and quality.

- By Andries Gouws

Plan before you plant

Before planting a pasture crop, several important decisions must be made. Consider the type of pasture required and when it will be needed, assess the soil’s chemical condition, determine whether adjustments are necessary, and select the most suitable cultivars for your environment. You'll also need to decide whether to plant annual or perennial species.

When establishing perennial forage crops such as lucerne, it is essential to correct soil pH, and calcium and phosphate levels before planting. Once these crops are established, making such adjustments becomes extremely difficult or even impossible. Legumes such as lucerne, medics, and clovers fix their own nitrogen from the atmosphere, so fertilisation efforts will focus more on phosphate, calcium, potassium, sulphur, and micronutrients.

Annual pastures such as forage sorghum and winter options such as oats are generally more tolerant of soil acidity and are managed much like grain crops. Phosphate does not move easily through the soil, so later applications are typically ineffective. Calcium is corrected through liming, while potassium and sulphur can be supplemented later.

Grass crops such as ryegrass require applications of nitrogen, potassium, and sulphur, with phosphate needed only in smaller amounts. Phosphate is applied only upon establishment while nitrogen, sulphur, and sometimes potassium must be supplemented once the grass has been mowed or grazed. Grass crops also respond well to foliar nutrition.

Finally, it is essential to conduct a soil analysis before establishing pastures to guide appropriate fertilisation and ensure optimal growth and productivity.