Pasture production and profits can be increased dramatically where extra fertilizer is used to lift the productivity of run-down pastures. This includes dry land pastures, cereal and pasture hay, irrigated pastures and high rainfall dairy pastures.
Table 1: Nutrient taken up by 1.0 tonnes of clover based pasture.
Some of these nutrients are recycled through livestock and via the dry material that is left behind. Nutrients such as nitrogen and potassium are very mobile and available, however phosphorus is not readily recycled once it is in the organic form For more details, please refer to our nutrient removal table.
We recommend conducting regular soil tests to monitor soil pH levels. Imbalanced soil can severely impact pasture and crops, by affecting the release of nutrients, and can allow fungus and bacteria to survive.
An acidic soil will produce poor growth, low nodulation and hence nitrogen fixation. It will also reduce the response that can be expected from applied nutrients. Good pastures will survive in a wide range of soil pH levels, however soil testing (top and sub soil) is essential to discovering the soil pH and predicting the response to applied lime. Some of the smaller testers are also good indicators. If the soil pH is below 4.6 in CaCl2, then apply lime (calcium carbonate) from a registered pit, at up to 2.5t/ha.
Heavy applications of calcium may upset the balance of xxx with potassium. Raising the pH too far may adversely affect the uptake of zinc, manganese or iron. If applying lime without cultivation, consider using lower rates and spreading the full application over two or three seasons.
Western Australian soils are very low in natural phosphorus, which is particularly vital to the growth and root development of legume-based pastures. If a plant is low in phosphorus early in the season, it can often never recover, leading to a false break to the season, dry stress, water logging, disease, insect attack and more. Find out more about the role of phosphorus in plants here.