Nutrient Management After Waterlogging

Why is Nutrient Management Critical After Heavy Rainfall or Flooding?

Heavy rainfall and waterlogged conditions can cause significant nutrient losses impacting both plant nutrient availability and soil nutrient reserves. Heavy rainfall can cause significant nutrient loss through both soil erosion and nitrogen leaching. Waterlogging can create anaerobic conditions which can cause denitrification resulting in further nitrogen losses. Denitrification is not only a further nitrogen loss process, it also generates a major greenhouse gas (GHG) nitrous oxide (N₂O).

Heavy rainfall can also cause soil erosion which reduces on-site productivity through the loss of fertile topsoil and nutrients and declines soil structure and water-holding capacity resulting in poor plant growth. Nutrient supplementation can be critical to getting your pasture quality back on track.

What should I apply?

If there is adequate ground cover fertiliser applications may be necessary to boost pasture growth and quality.  Nitrogen and sulfur applications are critical for quick pasture establishment, similarly, phosphate and potassium are also required. Soil testing will be vital to establish what nutrients are required.

Using a pasture blend with a high source of nitrogen, such as Pasture Pro M, can be essential to boost pasture growth by replacing depleted nutrients.

When should I apply after rainfall?

It is good to wait one or two days after heavy rainfall before applying fertiliser.  

If replanting/seeding is necessary plan to apply nitrogen once regrowth has restarted and there is adequate plant coverage.