Evaluating the sustainability of Sphagnum moss harvesting or farming versus horticultural peat using a multi-criteria decision framework

• Sphagnum and peat sustainability was compared using a multi-criteria framework • Researchers emphasized on environmental impacts more than other respondents • Sphagnum harvesting and farming showed higher overall sustainability • Peat outperformed Sphagnum only in profitability • Replanting improved the overall sustainability of Sphagnum harvesting As horticultural peat availability declines, alternative growing media are increasingly needed. Sphagnum moss has emerged as a high-quality substitute, yet its sustainability has not been thoroughly assessed. This study uses multi-criteria decision analysis (MCDA) to compare the sustainability of Sphagnum moss and horticultural peat. Sphagnum was evaluated either as harvested from natural sites with replanting or as cultivated on peatland farms. A panel of stakeholders and researchers assigned weights to the criteria, with biodiversity considered most important (39.78 points), followed by climate (26.81), costs (18.86) and employment (14.55). The results show that Sphagnum harvesting with replanting and Sphagnum farming achieved the highest overall sustainability scores (67.88–77.72 points), while harvesting without replanting scored lower (28.52–49.14). Horticultural peat received the lowest score (18.86). Based on these results, regrowth of Sphagnum after harvesting is essential to ensure sustainable harvesting, and Sphagnum farming offers a renewable and sustainable option for growing media production. Overall, Sphagnum moss represents a promising and more sustainable alternative to peat in horticulture, but further research and optimization are essential to realize its full potential. As the Sphagnum industry is still developing, there is substantial potential to improve field practices, particularly regarding harvesting techniques and regrowth management.