Page 16 - ALG 1.21

peat-free vs peat compost
The Peat
Debate
DEVELOPMENT OF PEAT-
FREE COMPOSTS
Few issues in horticulture and gardening have caused such controversy as the debate surrounding the use of peat. It would be rare to find any keen gardener or allotmenteer who didn’t have some awareness of the issue. In this article
I aim to give some background to the origins of the debate and to explain
how things stand today, using our own experience at Melcourt as peat-free manufacturers, to illustrate the points.
HISTORY – WHY STOP USING PEAT
During the late 1980s, conservationists became concerned about the loss
of peatland habitat and biodiversity. Undisturbed peatland hosts a unique flora and fauna that simply cannot
be found in other habitats and are
lost when a peatland is drained and harvested. These peat bogs need many years to recover and many are never returned to their original condition.
The UK government is now also very engaged due to the effect that harvesting peat has on the two politically important areas of carbon emissions and flood protection.
Carbon emissions: The 2008 Climate Change Act which set a target for greenhouse gas emissions to be cut by 80 per cent by 2050 has become one of the main drivers of government policy on peat. Research shows that peatlands cover just 3% of the world’s land area but they hold nearly 30% of all terrestrial carbon. It is estimated that damaged English upland peat bogs annually release the same amount of carbon dioxide as the emissions from 140,000 cars. As the carbon held within peat was removed from the atmosphere up to thousands of years ago, there is little doubt about the importance of peatland in the fight against climate change.
Flood protection: The importance of undisturbed peatland is increasingly being recognised in the defence against flood as these areas act as enormous sinks for excess rainfall. Peatlands can be managed to help mitigate flood risk.
In 2018 the UK government published its 25-year Plan for the Environment which included two targets for peat- replacement. The first was for all garden centre sales of compost to
be peat-free by 2020 and the second
that all growing media, including that used by professional growers, should be peat-free by 2030. Although the targets are voluntary and the first target has been resoundingly missed, the government also indicated within the Plan that should the industry not be seen to be making rapid enough progress on peat reduction, they would look at ‘further measures’ in order to impose change.
There are now very few intact low-land raised mires (the type of peatland from which horticultural peat is harvested) within England. Most of the peat used here comes from Ireland with smaller amounts from Germany and the Baltic States.
So, the case for peat reduction has been around for more than three decades but we are still seeing the legacy of an early drive to capitalise on what from some commercial companies perceived to be a wide-open market place for peat alternatives. Poorly developed peat-free products were launched with undue haste in the early 1990s and many were not very effective. Gardeners and growers alike were left with an impression that nothing was as good
as peat. Despite immense progress from many manufacturers in recent years, there are still those who are unfortunately very reluctant to stray from the peat-composts they have known for so long. Peat is a very hard act to follow but happily many people are now finding products that perform easily on a par with even the best peat-based media.
DEVELOPMENT OF ALTERNATIVES
Melcourt was founded by a forester in 1983 and uses forest-derived materials, bark and wood fibre as the basis of its growing media. Sylvamix® is named
to reflect its forest origins and is based on bark fines, wood fibre and coir. Various growing media manufacturers
Most of the peat used here comes from Ireland with smaller amounts from Germany and the Baltic States
developed other non-peat raw materials, such as coir, wood fibre, bark and green compost, sometimes as diluents for peat and others as complete replacements but to this day there are very few materials being used in any significant quantities. Each comes with its own set of challenges but the evidence of many years shows that they can be used to make growing media that are equally
as effective as the peat-based products they are gradually replacing.
MEASURING ENVIRONMENTAL IMPACTS – FRYING PAN
INTO THE FIRE?
Although the thrust of attention in this area has been on peat reduction for the reasons given, it is also recognised that all raw materials have an environmental impact. In recognition that the growing media industry was faced with various challenges on peat reduction and that progress was in their view too slow, the government set up a task force in 2011 to explore the barriers to peat reduction. The strength of the task force was its membership which encompassed
all sides of the industry from the conservation movement to retailers such as B&Q and Homebase, manufacturers and organisations such as the RHS and the National Trust as well as Defra. Born out of the work of the task force has come the Responsible Sourcing
of Growing Media Scheme. This is
an audited system that explores the environmental and social impacts of all growing media ingredients and scores them so that the purchaser can make an informed buying decision on the basis of a product’s score.
USING PEAT-FREE PRODUCTS
A well-designed peat-free growing medium will be no harder to use than a peat-based one and this is now routinely possible. We are yet to find an application for which a peat-free product cannot perform as effectively
16 Allotment and Leisure Gardener