The calculator was developed by the "P4 group" which was set up following a recommendation of the Sustainable Growing Media Taskforce (SGMTF).
This group was tasked with developing a tool that could be used to assess the environmental values of growing media.
The "calculator" enables manufacturers to measure and score seven criteria for the key materials used in products. The seven criteria are energy usage, water usage, social compliance, habitat and biodiversity, renewability, pollution and resource use. These scores are combined and weighted to give an overall score for the product.
Said Harper: "Version 1 of the calculator and supporting guidance notes and documents have been published on the HTA website and are now ready to be trialled.
"A number of GMA members have already nominated materials to test and we hope to feed these results back at a launch event on 30 June 2015 at Stoneleigh Park."
"The trial will allow manufacturers to see how the tool works and will guide the setting of benchmarks for the overall scores."
Ongoing work to set benchmarks will be overseen by a new steering group (the Responsible Sourcing Scheme Steering Group) which includes representatives from manufacturers, retailers, government, interest groups and growing media experts and will be meeting on 21 May.
The intention is to develop a 'business to business tool' for the industry and it is anticipated that once developed, the new scheme will replace the existing Growing Media Initiative.
The group is also working on a project to develop a standard methodology for the quality testing of growing media products.
Said Harper: "By having a standard test used by the industry, the aim is that all growing media will meet the same growing quality standards. A draft methodology has been developed based on the results of earlier studies. The results of the ongoing studies should be available by mid to late October this year. These projects demonstrate the industry’s commitment to ensuring we produce growing media that is not only fit for purpose and that is sourced with environmental considerations at its heart."
Data from a project that is mapping peat usage year on year is due to be released towards the end of April for 2014. It is thought that there could be an increase on the previous year’s figures due to unusually good weather conditions enabling longer harvest periods.
The GMA will review the findings at it summer meeting and will be formulating a response to the Government’s Policy Review which takes place over the summer.
More information at: www.the-hta.org.uk/gma