Garden talk: Why we all should be avoiding peat

If you go into a garden centre looking for compost, you’ll most likely find a big range of options, but unfortunately, most of it is going to have one thing in common: Peat!

But what is peat?

Peat is an organic material formed by the accumulation of partially decomposed vegetation that builds up very slowly in soils waterlogged with rainwater, where oxygen is not present. Over thousands of years, this build-up creates areas known as peatlands or peat bogs.

For the past few decades, peat has been the main material in commercially available composts, with several tons consumed every year. It’s not hard to see why - it sure has some features that make it an excellent medium to grow plants in - it’s lightweight, highly stable and pretty good at retaining water and nutrients; but many gardeners don’t realise the devastating impact that this has in the wider environment.

Why shouldn’t we be using it in our gardens?

Peat extraction, or mining, is simply unsustainable. Peat deposits build up over a really long time, increasing only by around 1mm a year, but commercial extractors typically remove up to 22cm of peat per year (1) - which means it is being depleted 220 times faster than it takes to form!

Alongside drainage for conversion to arable land, commercial peat extraction is leading to the destruction of peatlands. It is estimated that 80% of peatlands in the UK are damaged or destroyed (2), and we are now helping to destroy these habitats in other parts of the world as well.

And the problem is far greater than the depletion of a finite resource - Peatlands are not mere masses of decaying vegetation - they are incredibly rich, living ecosystems and one of the most valuable environmental resources on the planet.

peat extraction.jpg — Peat extraction in Southern Ireland. Photo by Markjhandel, 2003. Some rights reserved.

Why are peatlands so important?

We have all heard about the importance of tropical rainforests and the impact of deforestation, right? Well, we don’t have rainforests in the UK, but it’s no overstatement to say that the destruction of peatlands has just as big an environmental impact as the destruction of rainforests.

In their natural state, peatlands perform a number of important ecological functions, and provide countless environmental benefits, including carbon regulation and climate change mitigation, biodiversity protection, water filtering, flood risk regulation and scientific archive to name a few.

Let's look at some of these:

Peatlands are the largest land-based carbon store on the planet: Large amounts of carbon, fixed from the atmosphere into plant tissues, are locked away in peat soils, making them massive carbon sinks. Worldwide, peatlands store more carbon than all other vegetation types in the world combined, including all of the world’s forests (3).
When peat bogs are drained, and peat comes into contact with air, the carbon oxidises and is released back into the atmosphere in the form of CO2, where it contributes to climate change in a similar way to burning fossil fuels. In the UK, consumption of peat leads to annual CO2 emissions of more than 630,000 tonnes (4).

Peatlands are fascinating and unique wildlife habitats: Peatlands are incredibly valuable and biodiverse ecosystems, serving as homes to thousands of species of insects, plants and birds, many of which are now endangered.

Peat is a natural water filter: Peatlands reduce pollution levels in adjacent aquatic ecosystems by cycling elements, storing organic materials and trapping pollutants. As water derived from healthy peatlands is naturally of high quality and requires very little treatment, it’s a vital source of drinking water, providing Up to 70% of the drinking water in the UK (5).

Peatlands help to minimise the risk of floods: Sphagnum moss, often the main type of vegetation of a peat bog is able to soak up to eight times its own weight in water, helping to regulate natural water flows and preventing flooding.

Peatlands provide a unique archive of our cultural past: Thanks to their oxygen-free environments and slow rate of decomposition of organic materials, peatlands preserve information spanning thousands of years and provide valuable insight into the life of former cultures. It is estimated that over 20,500 archaeological sites may survive beneath and within peat in the UK (6).

Thorne Moor, a lowland peatland in South Yorkshire. Photo by Natural England, 1994. Some rights reserved.

What can each of us do?

Know what you are buying - Find out what’s in the compost you buy - unless labelled ‘peat-free’, multi-purpose composts are likely to be made of between 70% to 100% peat. Don't be fooled by catchy terms like 'organic' , and 'eco', as they don't necessarily mean peat-free.

Don’t buy peat-based composts - Avoid peat-based composts as much as possible - that goes both for bagged compost as well as potted plants sold in garden centres.
It may seem like a small bag and compost here and there will not make a difference, but collectively, it most certainly does - Amateur gardeners account for two thirds of the peat consumed in the UK (7) - twice as much as commercial growers!
And it goes beyond that, whenever you choose a peat-free alternative, as well as avoiding peat, you are creating demand for an environmentally-friendly option and helping to bring about a shift for more sustainable horticultural practices.

Ask for more peat-free alternatives at your local stores - Keep asking for more peat-free products wherever you shop for garden supplies. While there are some great options out there (as seen below), mainstream retailers will often have very little option to peat-based composts. Keep asking retailers, show them there is a demand! And then the more options are available, the more likely other buyers are to give it a try.

Help to raise awareness - promote peat-free to your gardening buddies, friends and family. :)

What is the alternative?

Peat-free compost. photo by hackney herbal, 2021.

Peat is only one of the many ingredients that can be used to produce potting compost. In fact, it only gained popularity in the past 40 to 50 years, before of which commercially available composts were predominantly made of loam (composted grass turf) or leaf-mould.

Alternative materials include animal manure, garden compost, leaf mould, wood waste, composted bark, wood fibre, coir, bracken, spent hops, and the list goes on. Many of these are by-products of existing industries, which is a huge bonus.

Coir, for instance, is a natural fibre extracted from the husks of coconuts. Although not local, it’s a waste product from the food industry, and a popular peat-substitute as it’s lightweight and has an excellent water-holding capacity.

If you are able to, making your own garden compost is, by far, one of the best choices. But there are also great ready-to-use alternatives out there.

If shopping on the high-street, the most commonly available peat-free option is a sub-brand of Westland (big gardening supplies brand) called New Horizon.

If shopping online, here are some great peat-free compost suppliers that we recommend:

Dalefoot - www.dalefootcomposts.co.uk
Dalefoot composts are made in the Lake District using mineral-rich wild bracken as a base, and very uniquely - sheep’s wool, for improved water retention and slow release nitrogen. They also have a vegan-friendly option that is great as a soil improver.

Fertile Fibre - www.fertilefibre.com
Fertile fibre produces a range of coir-based composts, including vegan (without any animal inputs) and biodynamic options.

Both of these are organic and certified by the Soil Association, which means all the materials used are sustainably sourced and free from agrochemicals and synthetic fertilisers.

When it comes to potted plants, unfortunately, most plant nurseries still use at least a percentage of peat in their growing medium, which makes it even more important to support those that don’t. Here’s a really great list of peat-free nurseries across the country.