It’s almost eight years since the Government’s Environment White Paper first set out targets to reduce the use of peat in growing media. However, the issue is still firmly on the agenda. Defra’s recently published 25 Year Environment Plan includes the policy goal of ‘Restoring vulnerable peat lands and ending peat use in horticultural products by 2030.’
The document warns that if sufficient progress is not seen on the introduction of peat alternatives by 2020, the government will ‘look at introducing further measures.’ However, other than committing to continue joint funding of industry research into peat alternatives and ‘support the industry as it puts the Responsible Sourcing Scheme for Growing Media into practice’, the 25 Year Plan include little firm detail.
This is where the onus falls on industry to drive the agenda. Defra’s key funding on the issue has been directed at the AHDB and ADAS managed project CP 138 – Transition to responsibly sourced growing media use within UK Horticulture, which is working with key suppliers such as Sinclair and ICL. The main aims are to construct a model of growing media that will produce the desired mixes at least cost, while evaluating responsibly sourced media blends as alternatives to peat in commercial crop production systems.
As well as the focus on peat, proposals from the Sustainable Growing Media Task Force stressed that all sources of material used in growing media should be sustainable. “Set up by the Horticulture Trades Association in conjunction with DEFRA, the Growing Media Association and other interested stakeholders, the Growing Media Initiative has responded by designing the Project 4 Responsible Sourcing and Manufacturing of Growing Media scheme,” explains Dave Steward of ICL. “This sets out to differentiate more responsible products from less responsible and enables comparison of the same material from different sources. This voluntary scheme has been designed to be practical, simple, robust, meaningful and cost effective.”
“There is now an acknowledgement of the key role of the industry in the ethical and responsible management of peat harvesting sites including the long-term commitment to aftercare and the positive benefits of restoration to carbon-sequestering, peat-forming wetland habitats,” points out Mark Hamill of Sinclair.
As the government hoped, customer demand is driving many of the moves to reduce peat use. “We are seeing many growers in this market using a peat reduced mix, normally around 30 per cent,” says Stephen Godfrey, Sales and Marketing Manager for Jiffy Products UK. “Most garden centre chains and multiples are looking to reduce peat and in many instances nursery stock and bedding growers are seeing good results from production in peat free mixes. We also supply the peat free coir grow-blocks for B&Q’s Easygrow product, and Jiffy, along with most growing media suppliers, are part of the GMA. At a European scale we are also members of Growing Media Europe.”
“Most growers are now using or transitioning to peat reduced mixes and those growing for organisations such as the RHS, Woodland Trust, Local Authorities and the National Trust are all using peat free mixes,” adds Mark.
“A few years ago it was the government’s 2015 target for all government and local authority contracts to be peat-free that drove sales, but that target has come and gone so now we find that the drive comes from growers making their own minds up about the ethics of continuing to use peat, or if they have a particular customer such as the National Trust that demands that plants are grown without peat,” explains Catherine Dawson, Melcourt’s Technical Manager. “Many of our customers are doing very good business with the National Trust which is expanding their plant offer.
“The technical pros and cons of peat versus non-peat are being studied by project CP138 but this is work that we had to do years ago when we started producing peat alternatives,” she continues. “Most growers don’t have the time or inclination to change their management practices greatly so we set out to ensure that our peat-free products could slot into growers’ current systems very easily. There are slight differences – but no greater than the differences that can also be found within peat-based media.
As well as the environmental and political reasons for adding other materials to growing media, there can be practical and technical advantages too. “Many growers are now seeing the benefit of adding peat-free components such as West+ wood fibre into their growing media, with regards to the quality and shelf life of the plants produced with these blends,” says Mark. “These peat reduced mixes actually provide superior performance to traditional high peat based growing media with a number of benefits such as air-fill porosity and water management.”
At the same time, there are some signs that as media attention on peat reduction has decreased over recent years, so too has the demand for peat-free products from some sectors. “For us, the interest in peat free and peat reduced substrates, and requests to supply them in the UK market, have reduced over the past five years or so, despite our continuous investment in machinery to manufacture wood fibre and other constituents, whilst also financing ongoing R&D work into more alternative materials,” says Hermann Konnemann of German-based Klasmann-Deilmann. However, he feels that the 25 Year Environment Plan is likely to see interest rising again.
“Around 65 per cent of the growing media used by the professional horticulture industry comprises peat; this represents about 0.72 million cubic meters of peat across horticultural markets,” says Dr Eleni Siasou, technical manager for growing media at ICL. “It will take time to switch to peat free media on a large scale. Peat remains the only growing medium that has been extensively studied by soil scientists and thus its properties are fully known and understood. The majority of plants thrive in peat-based media including pot and bedding plants. Growers are experienced and confident at growing their plants in peat media and in the management in terms of irrigation, nutrition, EC, AFP and general horticultural practices.”
Hermann also points out that increasing the use of peat-free media may actually increase horticulture’s environmental footprint in some other areas: “Certain alternative materials to peat may require more irrigation, at a time when fresh water conservation is being encouraged. More fertilisation might be required with certain alternatives and this in turn requires the use of fertilisers which carry an additional footprint.” Concerns are also mentioned on competition for wood-based products, such as where possible competition from the energy market might influence price or availability in the future.
“Until growers become more convinced of the long term availability, consistency, cost and performance of the alternative materials, then conversion to peat free or peat-reduced products will remain below its full potential. This could in part also to be due to dissatisfaction in the way that previous attempts to address the use of peat have been conducted. The recently developed Responsible Sourcing Calculator allows peat to be compared with alternatives on fair basis, and highlights the fact that alternatives to peat also come with adverse impacts. It’s still in its infancy, but with on-going work could gain wider acceptance.”
Fewer growers now mix their own blends of growing media, which gives manufacturers greater control of the end result and which, in turn, increases confidence in raw materials which may be included. “There are very few growers left who mix their own growing media,” says Catherine. “Labour costs have influenced this but it is often the replacement of the mixing machine which acts as the catalyst for the grower to turn to bought in ready-to-use products.
Mark believes that, “Less than five per cent of growers are now mixing their own growing media. The majority would prefer a mix which is pre-made to ensure efficacy, consistency and performance, as well as convenience. With our new state of the art factory at Ellesmere Port we can dose much more accurately than mixing equipment found on nurseries. It also takes the risk away from the grower as to whether all the components have been added at the correct rates. We also carry out a series of quality checks on every batch of growing media we produce which a grower wouldn’t necessarily be able to do on the nursery.”
These quality checks extend to raw materials, with materials of validated, guaranteed efficacy and consistency being preferred for professional use. “At Sinclair we manage all of our own peat harvesting sites to the highest of environmental and operational standards based on a wealth of experience,” explains Mark Hamill. “By its nature, peat is intrinsically safe and sterile owing to the conditions under which it is produced with low pH and low nutrient content. No single alternative organic material can completely replace peat as a growing media substrate, though our research has shown that we can replicate and actually enhance the performance of peat for a number of parameters using a multi-material approach. Our West+ fibre technology has been central to these developments. As regards waste materials, Sinclair does not use green waste in any of its mixes due to high level of inconsistency and poor performance results. There is no short cut in our view, green waste is not suitable for delivering high quality plant material.”
“Melcourt also doesn’t use green compost in its professional growing media unless the customer specifically requests it and we only buy from a PAS100 Quality Protocol certified source,” stressed Catherine. “Certification should ensure product cleanliness but we carry out extensive testing of our own on top of this to ensure that the material is fit for purpose. This includes screening for herbicides as there are still one or two active ingredients that can withstand the intensive composting that green waste undergoes.”
Klasmann-Deilmann does use green compost, but as Hermann explains, “TerrAktiv® green compost is produced in our own composting units and certified to the Dutch RHP standard for green compost. It is also controlled according to German RAL scheme. All input raw materials and the green compost itself are regularly analysed for residues and against general chemical and biological parameters. GreenFibre® is also manufactured in our own sites; made form FSC certified wood and specifically certified to the RHP standard for wood fibre.”
There is no doubt that the growing media industry is working hard to meet the environmental targets being set by politicians and consumers, but further research is needed to overcome a number of technical issues, particularly in certain sectors such as plant raising. “At ICL we are constantly exploring new responsibly sourced raw materials and testing their adequacy,” stresses Eleni. “We are participating in research projects, along with other industry and academic partners, for the development of the next generation of growing media, such as CP 138 and the N8 Agri-Food Programme – Developing and testing sustainable horticultural growing media for food crops, funded by the University of Manchester and ICL.”
At the end of last year, Klasmann-Deilmann presented its sixth Sustainability Report, and over the last few decades, the company has re-wetted and afforested just over 8,000 hectares of former peat production sites, or prepared them for agricultural use. “More than 3,800 hectares of this area are now natural habitats which permanently promote nature conservation and climate protection,” adds Hermann.
The Commercial Greenhouse Grower has been the horticultural market’s leading magazine for over 20 years.
21 Church St
T: +44 (0) 1622 695656
Contact: John Downey