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Fertiliser replacement after leaching of nutrients

Floods and heavy rains can remove essential nutrients from the soil. Replacing these nutrients with fertiliser helps tree and vegetable crops to recover.

With the likelihood of continued heavy rain, fertiliser rates are best split into frequent applications of small amounts.

This means the amount potentially lost with each rainfall event will be lower and the levels will be topped up sooner with the next application.

Vegetable crops

Gradual replacement of fertilisers is critical for recovery of a healthy root system. Heavy applications may cause further root damage.

Foliar applications of soluble major and trace elements may help kickstart plants until their root systems re-establish.

Tree crops

Three of the important nutrients for tree crops - nitrogen, potassium and boron - are prone to leaching from the soil and levels are likely to be low after high rainfall.

Adjust their fertiliser applications to make up for expected shortfalls. Typically rates are increased by up to 20% above normal. If you suspect damage to the root system after prolonged waterlogging, it's critical that you replace fertiliser gradually to recover a healthy root system. Heavy applications may cause further root damage.

Careful application of boron

Don't apply too much boron, especially on light sandy soils, since this element can easily reach toxic levels.