​A soluble salt for outdoor and glasshouse fertigation programmes

A foliar fertiliser for application to crops to help overcome magnesium deficiencies

Care is required, as this product can be phytotoxic to crops

Applications may be useful when conditions are very wet or cool where QuickTest Mg levels are less than 8-12

Magnesium Sulphate is a cost-effective way of supplying magnesium via fertigation programmes.  As a foliar application to broadacre crops it will provide a temporary relief of magnesium deficiency symptoms.  Applications may be useful when conditions are very wet or cool where QuickTest Mg levels are less than 8-12.

​Uses

Magnesium Sulphate is used as a soluble salt for outdoor and glasshouse fertigation programmes as well as a foliar fertiliser for application to crops to help overcome magnesium deficiencies.

Application rates and advice

For crops such as cereals, potatoes, and outdoor vegetables, Magnesium Sulphate is typically dissolved in water (2-5kg Magnesium Sulphate /100 litres water) and sprayed on when herbage magnesium levels are low or deficiency symptoms occur.

Care is required, as this product can be phytotoxic to crops, therefore ensure foliar applications are made early morning or in the evening to risk the risk of leaf burn.

Although soluble in water, Magnesium Sulphate may not be compatible with other products. For fertigation purposes (in the field or under glass), if applied continuously, use concentrations of 0.05 - 0.075% for soil media and 0.05 - 0.15% for soil-less media.

Actual application rates will vary according to farm type, climate, productivity, soil type and crop type.  Soil testing and fertiliser plans are available to ensure you use the right product at the correct rate.  Call our Customer Centre for information.

Magnesium Sulphate is mildly irritant, so care should be taken to avoid contact with eyes.

As with most solid fertilisers, Magnesium Sulphate can be stored over a season as long as it is kept in a cool, dry, well ventilated area. Store bags in a dry place ensuring they are tightly sealed.