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The Responsible Sourcing Calculator

The UK horticultural industry actively seeks to improve its sustainability wherever possible.

As part of this, the industry has examined its sourcing of growing media and drafted the responsible sourcing scheme to enable manufacturers and users of growing media to understand and measure how their choice of growing media materials impacts on seven criteria:

  • energy use
  • water use
  • social compliance
  • habitat and biodiversity
  • pollution
  • renewability
  • resource use efficiency

The criteria have been defined as being able to differentiate more responsibly sourced from less responsibly sourced material. It will enable users of the scheme to source materials more responsibly, which we hope will help to improve the sustainability of this part of their businesses.

Some of the decision criteria may appear arbitrary, but they have been chosen to account for complicated and variable situations, which can include global supply chains.

Click to download the calculator

Click to download the guidance notes (January 2022)

Anaerobic digestate Worked Example

Supporting documents

The following supporting documents for the calculator are available:

P4 Decision trees document

Social compliance ingredient rater v5

Annex 2 - self assessment questionnaire minimum requirements

Note re using the calculator

When using the calculator it may be necessary for you to apply a Microsoft Excel fix to correct an upgrade carried out by Microsoft in 2014. This will vary depending on which version of Office you are using.

If you find that you are unable to progress back through the workbook, this will indicate that the patch is required.

The fix can be found by clicking on the following link: