On Slab Media

On Slab Media is designed for artificial growing environments such as planter boxes.

It is different to potting mix in that it is an organic soil-based blend that is used for larger volumes and longer lifespans. Additional fertilisers may be required depending on the species being grown.

The growing media is laid in the top 300mm of the planter box as the growing media around the rootzone. Under this the remaining depth is filled with low organic drainage material to ensure that subsoil oxygen is adequate and to avoid anerobic conditions forming.

On Slab Media is designed to meet the requirements of AS4419:2018; Soils for Landscaping and Garden Use – Table 2 Low Density Media (On Slab)..

This product is only available in commercial quantities.

Product Information Where to Buy



  • Open blend for improved air-filled porosity.
  • Lighter weight than landscape soil blends.
  • Consistent inputs for reliable performance.
  • Contains organic matter for slow releasing organic nutrients and water holding capacity.
  • Added medium to coarse sand for improved permeability.

Application Instructions

  • Ensure there is adequate drainage from growing container.
  • Install waterproofing if required.
  • Install as the A Horizon to a depth of 300mm. For planter boxes greater than 300mm in depth a 2-horizon planting system should be used with a low organic subgrade (B Horizon).
  • Plant and mulch as required.