Peat is partially-decomposed plant material from bogs and fens. It is laid down over thousands of years in waterlogged ground. The consequently low oxygen level and the acidic conditions inhibit decomposition. Mainly due to the special sphagnum mosses which grow there, peat bogs are very good at retaining water. Peat has been used as a key component of compost for many years because it enhances the development of plant roots. It does this by improving soil structure as well as locking in moisture and essential plant nutrients. Many different alternatives to peat now exist, all of which are less damaging to the environment, as long as they are responsibly sourced.
Nationally and internationally, intact peat bogs and fens are hugely important carbon stores. They are amongst the most carbon-rich ecosystems on the planet and approximately 10 times more effective at storing carbon than forests. However they take much longer to develop and restore. Around the world, peat bogs have been disappearing at an alarming rate, including here in the UK where over 80% have been lost or markedly degraded. Degraded peatlands actually release large amounts of carbon into the atmosphere. That’s why peat needs to stay in a pristine bog not put in a bag!
By far the biggest commercial use of peat is in horticulture. Many gardeners remain unaware of the damaging effects of peat harvesting. It simply doesn’t make sense to destroy peat bogs that have formed over thousands of years to feed the plants in our gardens. Horticulture didn’t start the degradation of peat bogs – peat cutting for fuel and drainage for commercial forestry/animal grazing have done that – but, it is making a bad situation a whole lot worse.
When peat bogs are drained prior to commercial extraction, their finely balanced ecosystems are destroyed, rainwater run off increases, localised flooding is more likely and resilience to drought and fire decreases. Over 3,000 species of insect, 800 flowering plants and hundreds of kinds of moss, liverwort, lichen and fungi have been recorded at Thorne Moor and Hatfield Moor in South Yorkshire. Together they form the largest remaining area of lowland raised peat bog in the UK. Ilkley Moor has lost much of its peat bog but efforts are underway to begin to restore some areas. First steps involve gully blocking to prevent rainwater run-off. The next step is to replant with sphagnum mosses, which act like sponges and soak up the water. They are the key component of healthy peat bogs.
Yes, and by a large amount. Typically multipurpose composts contain between 70 and 100% peat. However, composts with reduced amounts of peat are now available from several of the big manufacturers. In other words, the approach by the horticultural industry to phase out peat seems to be by dilution not replacement. Some compost brands now state how much peat they contain on the bag so you can make an informed choice before you buy.
Although John Innes composts are loam (soil)-based, they still contain peat. John Innes potting composts numbers 1, 2 and 3 contain 7 parts loam, 3 parts of peat and 2 parts of sand (i.e. 25% peat) plus varying amounts of plant food.
The short answer is generally yes but not always. Depending on which peat-free compost you decide to buy, the cost could be a little bit higher or considerably higher. As more of us switch to using peat-free compost and there are more suppliers in the marketplace, the cost is coming down. Expect to pay around £6.00 for 60 litres of the cheapest peat-free compost. Also remember that some brands of peat-based compost are more expensive than others. Thompson & Morgans’ Incredicompost that did well in the Which? trials costs £9.99 for 25 litres or £18.99 for 70 litres! In other words, it is heavy on peat and heavy on price.
The higher price of some peat-free composts mainly reflects two things: (i) raw material and production costs, (ii) costs of research, development and testing. Only now is the same amount of effort going into developing, comparing and refining peat-free composts as went into peat-based ones many years ago.
Like all composts, it depends on which product you buy and what you want to do with it. If you simply want to buy the peat-free equivalent of multipurpose compost, choose brands which have multiple components and added plant nutrients. Two examples are New Horizon from Westland and Melcourt SylvaGrow all-purpose compost with added John Innes plant nutrients which is recommended by the Royal Horticultural Society. Just like peat-based compost, the best ones for germinating seeds may not also be the best for growing plants in containers. If you would like further info, please ask for a copy of our peat-free compost factsheet.
A number of local retailers now sell peat-free compost, although some of them may not stock compost all year round. They include
Old Bridge Nursery, Ilkley
Morten’s hardware store, Ilkley
Moss and Moor, Ilkley
Stephen Smith’s Garden Centre, Otley
RHS Harlow Carr in Harrogate
Courtyard Planters in Otley
B & TS Builders Merchants
Twin Locks Garden Centre, Gargrave
B & Q
If you know of any others, please tell us and we’ll add them to the list.
For nationwide retailers, always check whether your local branch has stock. Some major chains sell their own brand of peat-free compost at competitive prices. However, check what’s in it before you buy. It is unlikely to have undergone extensive testing. An exception is the Sainsbury’s product which performed very well in the most recent Which? tests.
At the present time, there is no legal requirement in the UK to prevent the sale or use of peat-based compost. DEFRA originally set a target of 2020 for a voluntary, industry-led end to the sale of peat-based compost to amateur gardeners. Like so many environmental deadlines, this one wasn’t met because DEFRA relied on manufacturers and retailers to drive change. There was no carrot and no stick.
However, things are changing more rapidly now. Many major national and international charities are pushing for an end to the sale of peat-based composts including the National Trust, the RSPB, Friends of the Earth, Plantlife and the World Wildlife Trust. The Royal Horticultural Society stopped using and selling peat a year ago. Throughout 2020, the BBC’s Gardener’s World has heavily promoted the use of peat-free compost and mentioned it in nearly every episode. More locally, Bradford Metropolitan District council (BMDC) stopped using peat several years ago and now makes its own compost from garden waste collections. According to Rebecca Pow, Minister for the Environment and Rural Affairs, the new UK Peatlands Strategy is due for publication soon.
Last but not least, there are now numerous brands of peat-free compost on the market so there is something for everyone.
Here in the UK, we’ve already harvested most of our peatlands to exhaustion. Efforts are underway to protect and preserve some of those that remain. Most of the peat currently being sold to amateur gardeners is imported from Ireland and the Baltic States.
Whilst there are many different brands of peat-free compost, there are only 3 basic types. The most commonly available type is based on coir, which is derived from coconut shells. New Horizon compost made by Westland is the best-known example. A second type of peat-free compost is made from green waste such as that collected from households by the local council. Very few commercial firms sell this type of compost as it is hard to maintain consistency from batch to batch. Green waste is highly variable depending on the season and where it is collected from. In 2020, Booth’s supermarkets sold Yorganics compost made from green waste. Pro-Grow, produced by the waste management company Veolia, is another example. A third type of peat-free compost is based on plant materials such as pine bark, bracken and/or wood fibre in various proportions. This is less variable than compost made solely from green waste. A small amount of coir is sometimes added to improve consistency. The best-known example of this type of compost is SylvaGrow by Melcourt. It is recommended and sold by the
Royal Horticultural Society. Please note that some coir-based composts may not be sustainable and any compost based on 100% coir is unlikely to perform well. Good coir-based compost suppliers will obtain their coir from a single certified source.
As well as organic materials like coir, wood fibre and green waste, the best peat-free composts will also contain inorganic materials such as grit, sharp sand, rock wool and/or perlite to improve their structure. Large and small particles are needed to produce a balanced compost. This provides the correct ratio of air and water and good drainage to promote excellent root growth. Several also contain added plant nutrients.
No-one wants to buy peat-free compost and then find it doesn’t perform as well as their usual compost. Some big commercial companies conduct comparative trials on their own products. The Royal Horticultural Society and Which? have also done extensive testing. The best of the peat-free composts are now almost certainly as good as peat-based ones for most purposes. However, you may find that adding some soil, sand/grit, leaf-mould or fertiliser is beneficial, depending on how you intend to use the compost.
As a general rule of thumb, find out what’s in the peat-free compost before buying it. If it contains only a single ingredient, you may be disappointed. Look for peat-free compost with several components and an explanatory label.
Peat-based composts are not all equal – it’s exactly the same with peat-free ones. Some have no added plant nutrients, some have enough for the first few weeks and some shouldn’t need any extra feed for up to a year. In many cases, this will be clear from the label. For example, none of the Dalesfoot composts require additional feed for a full growing season. Miracle-Gro peat-free all-purpose compost doesn’t need added plant food for the first 3 months whereas plants grown in SylvaGrow Sustainable or Westland New Horizon need additional feeding after the first 4-6 weeks. Incredipeatfree compost comes with a separate sachet of plant food. If the compost you buy is 100% green waste or coir, you will almost certainly need to add plant food from the start.
No. All traditional John Innes composts contain loam (soil), peat, grit-sand and added plant nutrients – the amount of peat is roughly 25% by weight. However, some peat-free composts such as Melcourt Sylvagrow now come with added John Innes nutrients. Always check the label.
Some peat-based compost is made using peat recovered from run-off water during heavy rainfall. This ends up in rivers and lakes from where it can be filtered off. Moorland Gold composts are made from this recovered peat by West Riding Organics Ltd. Fertile Fibre also sell reclaimed peat compost (see www.fertilefibre.com).
Always buy peat-free compost from a reputable manufacturer unless you’ve found a local source you know you can trust. For example, some councils make and sell compost from the garden waste they collect. At the time of writing, BDMC do not offer this service. Some small organic suppliers won’t be big household names but you can trust them as long as they are based here in the UK and are certified suppliers. A good example is Dalefoot Composts, a small firm based in the Lake District which makes a range of peat-free composts, some containing Herdwick sheep wool.
Ethical Consumer (www.ethicalconsumer.org) looked at peat-free composts in 2015 but hasn’t updated their website since then. They warn that some suppliers have poor ethical credentials and many still do. Most of the major commercial compost producers continue to promote and sell a range of peat-based composts. However, if we don’t buy their peat-free alternatives, we run the risk of confirming their prejudice that gardeners don’t want to switch to peat-free compost. If we want them to stop selling peat-based compost, we have to stop buying it and then the market for it will disappear.
Yes, although you may have to pay more as delivery charges can be quite high. Buying in bulk between several households can sometimes save money but be prepared to buy up to 20 bags, or a ton in an open-topped container
No. The important thing is that the ingredients are sustainably sourced and are harvested, processed and mixed in ways that don’t damage the environment or consume a lot of resources. Buying locally made compost if you can get it is great as it hasn’t clocked up many road or air miles to get to the point of sale.
Yes, several of them. If you’re a gardening enthusiast, you are probably looking for something more than a general or multipurpose compost. The most comprehensive peat-free ranges are produced by Melcourt, Dalesfoot, Growmoor and Fertile Fibre.
Yes and no. It depends what the compost is made of. Mulches are applied to the surface of soil to reduce water loss, suppress weed growth, protect shallow roots from frost and improve soil quality. Mulching also makes your garden look neat and tidy and can save time weeding and watering. Ideally use something like bark, wood chips, well-rotted manure or leaf mould that will persist and break down slowly over time. Composted garden waste also makes a good much. If your soil needs improving, add compost into the hole when you plant and mulch after watering. Lakeland Gold from Dalesfoot Composts is a bracken-based soil improver that can be dug in or used as a mulch. Natural Grower (https://naturalgrower.co.uk/) makes a Soil Association approved organic and vegan mulch which is a waste product from the use of maize to generate renewable energy.
Yes, but at the moment few companies make a peat-free ericaceous compost. Look out for SylvaGrow ericaceous compost which is widely available. Dalesfoot make an ericaceous compost made from sheeps’ wool and bracken. Growmoor make one with added seaweed. Miracle-Gro is launching a peat-free ericaceous compost this year.
Peat usage is not the only aspect of compost manufacture with environmental impacts. A new initiative by the Horticultural Trades Association (HTA) is seeking to assess all aspects of the compost supply chain and specifically assign scores out of 20 for each of: water usage, energy usage, social compliance, effects on habitat and diversity, pollution, renewability and resource use efficiency. A calculator is available on the HTA website which manufacturers can use to assess the environmental impact of the composts they produce.