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LCF Australia

Nutrient guide

Manganese (Mn)

A trace element that is often short on calcareous and alkaline sands, especially in loose seedbeds and dry conditions.

What manganese does

Manganese is involved in photosynthesis and in the plant’s defences against some root diseases.

Where it is often short

Deficiency is common on calcareous and alkaline sands, in loose or fluffy seedbeds and in dry conditions. In well-aerated, alkaline soils, manganese is oxidised into forms plants cannot absorb, so manganese applied to these soils can quickly become unavailable. Loose seedbeds give roots less contact with soil and let more air in, which adds to the problem.

Signs of deficiency

Leaves become pale and limp, with yellowing between the veins and grey or brown spots or streaks. In oats the condition is known as grey speck. Symptoms often appear in patches across a paddock.

Ways to supply manganese

  • Foliar sprays, often based on manganese sulphate, are widely used because soil-applied manganese can be tied up quickly on calcareous soils. More than one spray may be needed.
  • Seed dressings and fertilisers containing manganese are used on some soils.

Crop guides

What manganese deficiency looks like

Photos of deficiency symptoms. Where we do not yet have a suitable photo, we will add our own trial photo. Symptoms vary with crop, variety, soil and season.

  • Manganese deficiency in a cereal crop. We will add our own trial photo here.
  • Manganese deficiency in lupins. We will add our own trial photo here.

Photos may show other crops with the same symptom. Full credits: Image credits.

How LCF products fit

LCF Australia supplies compound fertilisers made by our manufacturing partner Lardmee (LDM), including Urea Plus and zinc and manganese sulphates, on enquiry. We also supply the Field Spears soil testing kit, which reads soil N, P, K and pH in the paddock. Which product suits, how much and when depends on the soil, the crop, the season and how you apply it.