Use of peat in growing media: State of the art on industrial and scientific efforts envisioning sustainability

Considerable efforts have been put in place towards more responsible peatland management and growing media production, trying to reach sustainability. Such studies have shown that restoring peatlands may be successfully achieved and will bring back habitats and biodiversity in areas previously submitted to peat extraction and plant communities. Meanwhile, the unique long term C sequestration function of peatland ecosystems can be re-established. However, the C footprint of peat extraction is still real, as long-term locked up carbon is released through exposition with oxygen; but the fate of C after peat usage and its interaction with the atmosphere is still a largely unknown field of peatland C cycle. Preliminary results indicate that raw Sphagnum fibers could be successfully used in growing media, diminishing largely the C footprint. Switching from peat to other components using compost and other industrial byproducts appears a valuable alternative towards sustainability and allows the use of suppressive microorganisms in these medium. However, peat alternatives may be limited because of overall availability and because of a growing demand for artificial media with the coming expansion of urban farming and superfruit (raspberry, strawberry, blueberry) production.