Last reviewed 3 August 2021

For decades, peat has been used in the UK as a growing medium for plants. However, with the growing recognition of peatlands as a carbon sink, the government’s long-awaited Peat Strategy has pledged to phase out its use. Laura King looks at why peat is used, and how organisations can move towards a peat-free future.

In 2011, the government’s policy paper, The Natural Choice: Securing the Value of Nature, set the milestone of reducing peat use in horticulture to zero by 2030. To achieve this, the government outlined voluntary phase-out targets, aiming for amateur gardening to be peat-free by 2020, and setting a non-compulsory target of 2030 for professional growers of fruit, vegetables and plants. While the 2030 target is still some way off, the missed 2020 target did not go unnoticed, and in April 2021 several prominent celebrity gardeners, experts, conservationists and scientists sent a letter to the environment secretary calling for a complete ban of products containing peat by the end of 2021.

The government’s Peat Action Plan, published in May 2021, recognised that the government’s voluntary approach had not succeeded and announced an intention to set absolute deadlines banning peat use in both amateur and professional sectors. A consultation on how to achieve this is expected in summer 2021, with an immediate focus on amateur gardening for which the government has committed to a ban by the end of the Parliament (nominally spring 2022).

Why is peat used in horticulture?

The use of peat in horticulture has been popular since the 1960s, and by the 1990s peat was the dominant growing media used in the UK. As a growing medium, peat confers a number of benefits.

  • It provides a fine, yet open structure that facilitates good air and water retention, promoting healthy root growth.

  • As the pH of peat is low (it is acidic), lime (an alkaline) is added to raise the pH to the required level. This means that the pH can adapted and altered to suit optimal pH ranges for specific types of plants.

  • Peat has relatively low concentrations of nutrients, and so any required plant nutrients can be added.

On top of its physical benefits, the horticultural industry often operates with tight margins. Plants sold in supermarkets, for example, are often loss leaders and so nurseries and professional growers require a medium that is relatively cheap while producing consistent results. Peat can offer both these qualities.

Why is the use of peat ending?

Peatlands provide a number of benefits to nature and society. When in-tact they can reduce the risk of flooding in nearby communities by slowing the flow of water off the hills, and can improve water quality in rivers and reservoirs by reducing erosion. They also provide a unique habitat for certain birds and plant species.

The importance of peatlands in efforts to reduce climate change has also come into much clearer focus. Peat is made up of organic material that has only partially decomposed with the result that it acts as a store for carbon. This means that although they only make up 3% of the world’s land area, peat accounts for almost 30% of the world’s stock of carbon (twice that of forests globally). When peatlands are damaged or drained much of this stored carbon is lost. Indeed, the UK’s peatlands are thought to be emitting 10 million tonnes of carbon per year. Peat in well-functioning bogs accumulates at a rate of around 1mm per year, and so it takes thousands of years to form the deep peat, and as such, once excavated or degraded, it is not quickly regenerated.

What are the alternatives?

As a growing medium, a number of alternatives to peat exist. These include materials such as bark, wood fibre, coir, as well as more novel materials such as bracken and sheep’s wool. Royal Horticultural Society trials have shown that such materials can be used successfully instead of peat.

Peat can also be used as a soil improver or mulch. This is one area where replacements are easily found. For instance, soils can be improved using plant compost, or well-rotted manure. Peat replacements for mulching can include wood chippings, leaf mould or non-biogradable alternatives such as decorative aggregates and stone.

What can organisations do?

Understand the current situation

  1. Understand where peat is used within operations. This could be in-house use of peat, as well as when plants are bought in for annual planting.

  2. Speak with grounds staff and contractors to drill deeper into peat use and how much information is held on what growing mediums are being used (labelling developed by the Growing Medium Association is due to be launched to help with understanding the composition and sustainability of growing media).

  3. Look at the supply chain. For example, if grounds maintenance is contracted out, what is the policy of the contractor when considering peat use? How do they vet their suppliers?

  4. Work with grounds staff to identify if there are any areas peat is being used that could be done differently. For example, by reviewing mulching or soil improvement practices.

  5. Collate the information and identify where there are gaps in knowledge.

Outline the company’s position

  1. Consider the company’s position and map out the risks of using peat, as well as opportunities in moving towards a peat-free operation.

  2. Establish costings. One of the barriers to peat-free growing medium can be cost, so consider budgetary implications, and whether short-term cost increases are outweighed by longer-term benefits such as reputation management.

  3. Develop a strategy. Having a strategy in place will make it easier to consider purchasing options and to work with suppliers to develop solutions.

  4. On the back of the company’s strategy, draft a peat policy. A policy might include the following.

    1. Where gaps in knowledge have been identified, outline a roadmap for understanding peat use within the organisation.

    2. Set targets for complete elimination of peat.

    3. Stop the purchase of peat or peat-based products for direct horticultural use (for example as a potting compost) unless there are no viable alternatives.

    4. Work with procurement teams to include terms and conditions in contracts that work towards eliminating peat use. For example, by only using contractors and suppliers that have their own targets to eliminate the use of peat.

    5. If there are certain areas of the operation where peat is critical identify how the organisation will work with nurseries and growers towards changing this situation.

Work with contractors and suppliers

  1. Communicate with suppliers and contractors about the intentions of the company and work with them to develop a roadmap for targets. They might have genuine concerns or barriers that will need to be considered as part of the change and should be able to provide updates on industry developments. Communication is also key to enable suppliers to develop strategies to meet changing requirements. For instance, they might need to work with their own suppliers to address peat use, or research alternative ways of working.

  2. Set up an open dialogue to look for solutions to reducing use. An example might include peat-free pilots. These could be used to identify plants that do best on peat-free growing mediums, or trialling other methods for landscaping.

Summary

The use of peat in horticulture is coming under increasing scrutiny and so organisations with ground maintenance responsibilities should have a clear policy on peat use. This might include:

  • identifying gaps in knowledge

  • setting targets towards peat elimination

  • working with contractors and suppliers to outline realistic zero peat roadmap.