Alternatives to Peat in gardening
Why use peat alternatives ?
Over the last century or so, the vast majority of the UK's peatbogs have been damaged or destroyed just to provide commercial and amateur gardeners with cheap peat for use around the garden.
The peatbogs around the UK provide low-nutrient environments for a large variety of unique wildlife, plants and invertebrates and these have been endangered due to peat extraction.
Peat takes hundred or thousands of years to build up and cannot be considered as a sustainable resource.
Peat has been used around the garden as:
- A soil improver.
- A growing medium (including potting compost).
- A mulch.
But there are available sustainable alternatives for all of these purposes and in recent years, as the supply industries have moved away from extracting peat, the apparent cost advantage of peat has diminished.
Whether you are looking for a purchased or 'home made' alternative to using peat, there are an increasing number of options available. Even modern 'peat based' compost and other peat based products tend to include a percentage of peat-alternatives so the actual peat used will be less than in the past. If you are purchasing a 'peat-based' product, check that:
- It includes a reduced level of real peat.
- That any peat used is not from a UK lowland peatbog nor a Site of Special Scientific Interest (SSSI) - if the peat originates from outside the UK, the packing should normally state '...SSSI or original country's equivalent..'.
If the packing does not clearly state the level of peat alternative used or the origin of any peat used, the only way to have a clear conscience is not to buy it.
The UK government has set a target for 90% of 'soil conditioners and growing media' to be peat free by 2010, and there is currently no reason why the ordinary gardener cannot help this by now using peat-free alternatives.
What are the alternatives to using peat?
One thing to watch for is that some peat-alternatives are not as sterile as peat, they may contain weed seeds or fungal spores (especially bark/wood products), however, in purchased products, these tend not to be a problem other than possibly looking untidy - with home-produced products, one can never be too sure what was included in it.
To look at the alternatives to peat, we will break it down into the different uses for which peat has been used:
A soil improver.
Despite its use as a soil improver, peat does not actually help much in most soils as it is low in nutrients and hard to work into the soil.
Alternatives can be any organic material in a suitable condition (i.e. normally rotted down), these include:
- Garden compost.
- Composed bark/wood chippings.
- Farmyard manure - see our page on organic manures.
- Leafmould - by keeping a heap of fallen leaves (not evergreens) separate from the normal garden compost heap, the leaves will rot down so that after two years, the leafmould can be sieved and added to the soil as an improver.
Any of these organic materials is, in fact, better in most soils than peat as they introduce nutrients as well as improving the soil structure (which affects the drainage/water retention).
A growing medium (including potting compost and growbags).
Most peat based growing media have historically use peat as part of a mix (for example, using peat with loam and sharp sand), rather than peat on its own. The peat mainly helps create the structure of the medium which helps root growth, drainage etc., peat does not contribute any 'plant foods' to the mixture and this encourages the roots of the plants to grow searching for those 'foods'.
Alternatives to peat as a growing medium include:
- Garden compost - sieved, well rotted garden compost provides a suitable alternative to peat in most growing media, although the fact the compost adds nutrients will mean that the mix ratio will need to be adjusted (i.e., compost is not a straight replacement for peat).
- Composted bark - actually it is usually 'composted forest products' i.e. it includes wood chips, sawdust etc. Providing that it is well composted, this provides a structure very similar to peat, although it does contain nutrients thus necessitating 're-balancing' of the mixture.
- Coir - made from the waste of coconut fibre production, disposal of this waste was, in fact, causing its own environmental
problems before it was introduced as a peat substitute. Left to rot down, Coir ends up as a crumbly substance which when used in
mixes for potting compost improves porosity and moisture retention in a very similar manner to peat.
Coir is also available as small blocks for growing individual plants which can be planted out without disturbing the roots.
Peat is often used to increase the acidity of ericaceous compost, however composted heather, bracken or pine needles will have the same affect.
Peat growing pots are popular as they can be planted directly into the soil without disturbing the roots once the plant has become established in the peat pot.
The same results can be achieved by using paper or cardboard pots (not waxed). In fact, alternative pots can be simply made using old newspapers formed around a hollow pipe and the ends 'tucked up' to close one end of the paper tube - there is at least one special tool on the market for making your own paper pots from newspapers.
There are so many alternative mulch materials, that there is no excuse for using peat and, anyway, peat is a poor mulch material as it tends to dry out and is then carried away by winds. A 'new' alternatives mulch material is Cocoa-shell (a waste product from the production of chocolate), so again its use is very environmentally friendly.
Other mulch materials can be either organic or non-organic, such as:
- organic materials - manure, grass clippings, leafmould, bark, straw or stalky material etc.
- non-organic materials - black polythene, stone chippings or crushed slate etc.
See our page on mulching for more information.