Peat-free compost choices

RHS Advice Guide
Peat-free composts are now widely available, making them an excellent choice both for your plants and the planet. Here we look at how to choose suitable peat-free composts for all your garden needs.


Many peat-free composts are based on coir or composted bark

Quick facts

Peat-free compost is widely available and more sustainable than peat-based compost

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Going peat-free helps to conserve precious peat bog habitats and combat climate change

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‘Environmentally friendly’ and ‘organic’ composts aren’t necessarily peat-free

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Benefits of peat-free compost

Going peat-free is great for the environment, and as new mixes have been developed for every need, your plants will thrive too.

Preserving peatlands is vital for the unique they support, as well as for the wider environment and climate. These habitats are important carbon stores and damaging them, including by draining them for peat extraction, releases carbon dioxide, contributing to climate change. Peatlands also play a key role in soaking up excess rainfall, helping to prevent localised flooding.

Along with increasing availability of peat-free composts, the quality has improved considerably in recent years too. So if you’ve had a go with peat-free in the past and had problems, it’s well worth trying again to find your perfect peat-free mix.

Despite previous government commitments, there is currently no legislation in place banning peat use in horticulture, so the timeline to end the use of peat in horticulture remains unclear.

Meanwhile, the RHS remains committed to a peat-free future for horticulture. Read more about our peat-free policies across all RHS operations, including Shows, Gardens and Retail, which came into force from 2026.

To ensure the you choose is sustainable, look out for the Responsible Sourcing Scheme (RSS) logo on bags. You can search the RSS website to find the traffic light rating of the compost, which is assessed based on seven environmental and sustainability criteria.

Now is a great time to join us and get started with peat-free growing.

Selecting peat-free composts

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Always choose a to suit the plants you will be growing, such as or long-term container plants. Some plants, like or acid-loving plants and houseplants, need specialist mixes. With the expansion in the range of peat-free options, you will be able to buy peat-free versions of any type of compost.

When deciding between peat-free composts, look for information on the packaging about how to use it and which plants it is suitable for. The packaging may also recommend the use of specific fertilisers with that compost: this is not a marketing ploy, as different formulations have different balances of . Use either the recommended product or one with a similar nutrient balance – compare fertilisers by checking the NPK ratio and the trace-element content quoted on the packaging.

The following peat-free options may be especially useful:

  • Multi-purpose and – most major manufacturers produce peat-free multi-purpose products, as well as mixes designed especially for seed sowing. Some multi-purpose composts contain added John Innes, these can work well for containers that will be home to plants for more than two or three years. As traditional-recipe John Innes contains peat, it must say peat-free on the bag.
  • Ericaceous compost – the choice for ericaceous (acid-loving) plants is more limited, but these mixes have a lower . Used with an ericaceous feed, these products will provide all the nutrients and trace elements your acid-loving plants need. 
  • Carnivorous plant compost – since many carnivorous plant species are at home in peat bogs, they are traditionally grown in a peat-based mix. However, more sustainable peat-free options have been developed in recent years. Mixes usually contain milled , other fibrous materials such as sustainably-farmed sphagnum moss, combined with , or . In fact, RHS research is showing that some types of carnivorous plant can be grown more successfully in peat-free mixes than in peat.

Peat-free buying tips

  • If the bag doesn’t say peat-free, then it most likely isn’t
  • Words such as ‘environmentally friendly’ and ‘organic’ may lead you to think a product is peat-free, but they don’t necessarily mean that it is
  • The price of a tends to reflect the quality of the ingredients, and the amount of added fertiliser 
  • Check the information on the bag to see if it’s recommended for particular uses or plant groups (such as seed sowing or growing plants)

When buying plants, you may also wish to consider choosing plants that have been grown peat-free. Our peat-free nursery finder is here to help you source plants raised 100% peat-free. RHS Plants online and the five RHS Garden Centres also stock a wide range of 'no new peat' plants

How to use peat-free composts

Peat-free composts can look and feel very similar to peat-based composts. However, they do need to be treated differently, and the watering and feeding requirements in particular may need changing if you were used to growing in peat.

It is best to try and use up your peat-free within the you bought it. Composts that are left longer than this can start to break down, meaning plants grow less well compared to using fresh compost. Some brands, including Melcourt, include the production date on the bag, so you can check exactly how fresh it is. 

If you have compost that's over a year old you can add this to your home compost, use it to bulk out large planters, or add to beds and borders as a .

Main ingredients of peat-free compost

Peat-free potting composts contain blends of various organic (plant-derived) materials – such as composted , coir, wood fibre and composted – sometimes mixed with inorganic materials such as grit, and loam. All these materials have their own physical, chemical and biological properties that are different to those of peat, so it is worth trying a few different mixes to find one that suits your garden and the plants you grow.

Many of the ingredients in peat-free composts were previously considered waste from other industries, particularly the timber and coconut industry. These ingredients get a new life, and trees or coconut palms are not being grown for the compost industry, contributing to the sustainability of peat-free mixes.

Some of the most commonly used organic ingredients are:

  • Wood fibre – treated wood chips, with different treatments resulting in different materials depending on needs. Steam-treatment will give a very loose material, while crushed or milled wood fibres give a more fibrous product that can improve drainage. Depending on their treatment, wood-based mixes can be tailored to the requirements of many plants.
  • Coir or coconut fibre – the inner husks of the coconut which would otherwise be a waste product, mainly imported from Sri Lanka and India. Coir has excellent water-holding abilities and its mix of fine and coarse fibres make it light and porous, providing good growing conditions. However, it doesn’t hold as well as some other materials.
  • Composted bark – most often the bark of pine trees, again this component can be treated in different ways to give the bark certain properties for different uses. Bark is very stable and porous, so can help add air to a compost.
  • Green waste – many local authorities and private companies collect and anaerobically compost green waste. The resulting compost tends to have a high nutrient content but can be very variable throughout the year without careful management. Green compost is subject to PAS 100 standards, which ensure that the composted materials adhere to specific criteria and a minimum quality level. 

Top tip

Home-composted food and garden waste is really useful as a mulch or soil improver – don't use bagged potting composts on your beds and borders.

Other ingredients
Research is ongoing into a number of materials that, if locally available, may be useful ingredients in blended products, such as arable straw waste, sustainably farmed sphagnum moss, bracken, wool and paper and cardboard production waste.

Home-made potting compost
You can mix your own peat-free potting compost using home-made garden compost, leafmould and inorganic materials (loam and sand). This has the benefits of being very low cost and having a much smaller carbon footprint than buying bagged compost, but the results can be very variable. It can be difficult to standardise the pH, moisture retention and available nutrients in your compost throughout the year, and to ensure that the final mix is weed-free.

Home-made potting composts are best avoided for seed sowing, because of the potential for them to contain fungi that harm or cause damping-off disease.

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