Peat is formed over long timescales from partially decayed plant material under waterlogged conditions in wetland habitats called peatlands. Because of this waterlogging, the plant material doesn’t decompose very much, so peat is incredibly rich in carbon, but usually acidic and nutrient poor. This limits the types of plants that can grow on peatlands.

Three main peatland habitat types are found in the UK: fen, blanket bog and raised bog. However, there are many more peatland habitats that can look quite different from each other, from mostly treeless blanket bog in the uplands to fen carrs covered with dense vegetation in the lowlands.

Peatlands cover around 10% of the UK land area and can be discovered in the most remote corners of the country, but also near major centres of human population. As iconic landscapes, peatlands offer breathing spaces for millions of people, support livelihoods and provide a sense of place for many communities. Peat harbours a rich cultural and historic archive with preserved artefacts and a wealth of information about our changing environment and climate. Peatlands are important source catchments for drinking water and also have a role in the regulation of water flows. 

Unfortunately, most UK peatlands have been historically managed in a way that has left them in a damaged state, with an estimated 80% in some way degraded. At least 94% of UK raised bogs have been lost entirely due to changing land use, including peat extraction for horticulture. This involves draining the peatland and stripping away the living layer which forms peat.

Peat forms naturally under the right conditions, in areas where water levels are close to the ground surface. However, peat forms over very long timescales, at a rate of approximately 1 mm per year. At this rate, it takes 1000 years to accumulate 1 m of peat! 

If a peatland is drained, peat will not accumulate. In the UK, an estimated 80% of peatlands are in some way degraded, which reduces the area suitable for peat accumulation further.

To be a renewable resource, peat would have to be extracted at a lower rate than it can form. With such slow accumulation rates, the renewability of peat is not relevant to the timescales of our modern society and peat should not be considered a renewable resource. 

Blond peat (sometimes also called white peat or Sphagnum peat) is the topmost layer of a peat bog. It is made up of partially decomposed Sphagnum mosses and other plants. As it is still in the early stages of decomposition, it is usually light brown or yellowish in colour, fibrous and airy. Blond peat is acidic and low in nutrients.

Young peat is a broader term describing peat at an early stage of decomposition, which usually includes blond peat but can also refer to other fresh peat deposits.

To harvest blond peat, methods like sod-cutting or surface milling are used after the top layer of the bog is drained and cleared. Such methods destroy the functioning of the peatland and are not sustainable. 

Even if a peatland is rewetted after harvesting peat, this is an expensive process and the surface vegetation that forms peat will be lost. It may take decades before the peatland can start accumulating peat again, so a few years will not be enough to build blond peat for harvest.

Yes. More peat is disappearing than is being formed both globally and in Europe. Regardless of the quantities extracted for horticulture alone, we cannot ignore the fact that enormous losses are also occurring due to unsustainable agriculture and forestry on peatlands. 

No peat extraction method is sustainable, because along with peat, peat-forming ecosystems are also destroyed. Furthermore, the area of degraded peatlands that is under restoration to peat accumulating ecosystems is still negligible compared to the area degraded by peat extraction.

It may sound like a good idea to use extracted peat for restoration elsewhere, but unfortunately it does not work very well. Peat develops in specific conditions over long timescales. Excavating peat disrupts the structure that has been built up over thousands of years. It also dries the peat, leading to a disruption or loss of established biogeochemical processes within peat, including loss of carbon as the peat exposed to oxygen starts decomposing. 

Peatland restoration works best if the hydrological function of a peatland is restored, which allows peat to regenerate again in-situ. Moving peat from one site to another does not re-create the conditions required for restoring the functioning of the peatland.

Sphagnum moss has similar physical properties to blond peat and can be used as a growing medium. How damaging it is depends on how it is sourced. 

Sphagnum farming is currently being trialled in the UK. It is a method of re-wetting previously damaged peatlands and growing Sphagnum for harvest, which helps to retain carbon stocks in the peat whilst delivering an economic return for growers. 

The Sphagnum Farming UK project trialled growing Sphagnum under a range of cover treatments and solar-powered irrigation regimes and tested the product in growing media. Companies like BeadaMoss® are using sustainably micro propagated Sphagnum grown in glasshouses to develop techniques for producing sustainable Sphagnum growing media as an alternative to peat for use in horticulture.

Brands like ‘Moorland Gold’ source their peat from filters that remove eroded peat from runoff before it enters reservoirs. The product is marketed as a sustainable, natural and environmentally friendly alternative for gardeners who wish to avoid using excavated peat. However, peat runoff occurs in significant amounts where the surrounding peatlands are damaged or degraded, and unable to effectively absorb rainfall. Drainage, burning and overgrazing can damage surface vegetation and expose bare peat, which is vulnerable to erosion by wind and water. The resulting surface water runoff carries peat sediment into watercourses, where it is harvested from. Healthy, intact peatlands on the other hand absorb and store rainfall and would not produce significant amounts of peaty runoff. Harvesting peat sediment for commercial purposes is a practice that profits from degraded peatlands, and is therefore not sustainable. 

Fortunately, sustainable horticulture is achievable (and necessary), with huge progress made in recent years. The IUCN UK Peatland Programme publications ‘Peat-free Horticulture – Demonstrating Success’ and its more recent addendum celebrate wide-ranging successes in peat-free horticulture and explore opportunities for a thriving and lasting horticulture industry as well as a rewarding gardening experience. Both publications include case studies from producers, manufacturers and retailers who share their experiences with peat-free growing media and moving towards peat-free gardening.