Calcium – the forgotten nutrient

News March 25, 2021

Could a Calcium deficiency be holding back your forage production?

Growing good quality, high-yielding grass, and forage are at the heart of any successful dairy enterprise. ‘Milk produced from forage’ often cited as a vital key performance indicator for any business looking to drive forward efficiency and profitability.

But to grow quality grass, you need healthy soil. Therefore, measuring nutrients in your soil and addressing any deficiencies can be the key to unlocking higher grass yields. The tendency to use very basic soil tests, which simplify soil analysis to only include four metrics, can be detrimental. Instead, choosing a more detailed soil report will help you develop a better understanding of your soil’s nutrient levels. This information enables you to start identifying what might be limiting the potential of your forage, including inadequate Calcium supply.

Choose the right material

The quality of agricultural lime you use is paramount. Unfortunately, too frequently a product is delivered on to the farm which is purchased on price and not the specification. Ultimately farmers and growers must take responsibility for what they spread on their land. However, the trade also has its part to play in ensuring they know the correct legal specification for agricultural lime. This has led the UK Agricultural Lime Association (ALA) to set up the Aglime Quality Standard (AQS). The AQS ensures that all participating members meet the 1991 Fertiliser Regulations standard for lime as a minimum. In addition, it measures the Calcium and Magnesium content of lime as well as the reactivity. This quality standard endorsed by the AQS logo gives farmers confidence in the quality of the agricultural lime that they purchase.

Do you need mag lime?

Soils low in pH are prone to Magnesium deficiency, as well as light, sandy soils and shallow chalk soils with low organic matter. High levels of potassium in soil caused by Potash-rich soils or overuse of Potash fertiliser, also reduce the ability of plants to take up Magnesium.

Magnesium is another often-overlooked nutrient and yet it is essential for normal plant growth and a vital ingredient of chlorophyll; the green plant pigment that gives leaves their colour and enables photosynthesis. Magnesium is also important for Phosphate and Nitrogen metabolism,
as well as being a key component for protein synthesis. A detailed soil test will identify any requirement for additional Magnesium.