Stardust Earth is a New Zealand supplier of biochar-based soil amendments.

What is biochar? Most simply, biochar is charcoal destined to end up in the soil.

Biochar has a wide range of benefits to the soil and plants.

Research has confirmed benefits that include:*

  • Reduced leaching of nitrogen into ground water.
  • Possible reduced emissions of nitrous oxide.
  • Increased cation-exchange capacity (CEC) resulting in improved soil fertility.
  • Moderating of soil acidity.
  • Increased water retention.
  • Increased in beneficial soil biology

Biochar’s microscopic honeycomb structure creates a habitat for billions of soil micro-organisms that work to benefit the plants.

Biochar can also increase CEC resulting in improved soil. The CEC of  is a measure of its ability to hold and release plant nutrients. By increasing it, biochar can make the soil more fertile.

Biochar can also moderate soil acidity, creating better growing conditions. Biochar also helps the soil to retain moisture, meaning less watering, increased drought tolerance and more even availability of water to plants.

Finally, biochar lasts in the soil for hundreds to thousands of years, continuing to help plants grow the entire time and removing that carbon from the carbon cycle and helping to mitigate climate change.

It seems like a lot for simple charcoal but biochar has been proven to work in soils around the world for hundreds of years. This includes NZ "para umu" soils created by Maori using traditional gardening techniques.

Because of the carbon emissions of long distance transport, we only supply within New Zealand.

*NOTE all biochar is not the same. Using fresh, raw biochar that has not been aged or 'enlivened' by composting with other material may not be beneficial to the soil in the short term.