Agslag Agricultural Slag


Tarmac AgSlag is a high quality, calcium rich product providing essential nutrients to soils in a slow release form.

Used as a high-quality agricultural fertiliser since the 1920s with outstanding results in providing nutrients to agricultural soils. Maintaining a constant level of phosphate release over long periods, AgSlag only needs to be applied every two to three years depending on the soil pH-value and phosphate response. This saves significant time and cost compared to the annual application of chemical fertilizers whose phosphate levels diminish during the year.

  • Maximise yields of cultivated crops and pasture
  • Improve soil texture
  • Neutralize high soil acidity.

Proven performance

The slow release of nutrients enables AgSlag to provide prolonged effective treatment making it unique in its class. 

  • Neutralising value of typically 50% - improving productivity of acidic soil
  • Provides a release mechanism for soil-locked phosphates
  • An effective source of hydrated lime
  • Produces thick, verdant swards on grassland pastures and increases the palatability of grass
  • Boosts clover growth increasing the quantity of available nitrogen
  • Improves general well-being of livestock
  • Suitable for use on organic farms
  • Safe to handle and easy to spread
  • Factory conditioned to optimise particle size and reduce windborne loss
  • Applied using a conventional spreader therefore avoiding generation of airborne dust
  • Enhances the permeability of soil leading to improved air and water circulation