A CPS News article: Peat-free composts by Stephen Morley

Why not use peat?

More specifically, why not use Sphagnum moss peat, which is what we are talking about when we talk about peat for carnivorous plants, especially considering that it is an excellent growing medium for most carnivorous plants, it's easy to work with, is cheap and freely available? And, of course, we have always used it haven't we?

Well, Sphagnum moss peat is formed from the remains of partly decomposed Sphagnum mosses that have built up in bogs over hundreds of years. This peat is formed very slowly, in cold, wet, waterlogged conditions which prevents decomposition of the moss, and the result is a build-up of lovely brown peat with a cap of living mosses and other plants such as heather, cotton-grass and cranberry. This bog habitat supports a wide range of specialised and rare plants and animals, including many that we know and love such as sundews, bladderworts and butterworts, as well as many butterflies, dragonflies, reptiles & birds. Peat is a valuable historical and archaeological resource, providing pollen records which give us information on land-use, vegetation & climate change over the last several thousand years, and help us predict future changes. Peat also happens to be one of the best "carbon sinks" around, locking up CO2 to help combat global warming.

Peat is a desirable commodity. It has traditionally been cut for thousands of years on a small-scale by locals to burn on their fires to cook, and to heat their homes. The small-scale use does not adversely affect the bogs, and is in fact desirable as it continually opens up small areas of bare peat allowing regeneration by bare-peat colonisers such as Sphagnum tenellum, and creating a succession of varied habitats. The problem is the commercial extraction of peat, both for fuelling peat-burning power stations in Ireland and for making potting composts. This commercial extraction involves scraping off and dumping the top living layer of the bog, then mining the lower layers with large mechanised machines which can strip thousands of tonnes a day. To allow these machines to operate, the bogs need to be drained to dry them out enough so that the machines do not sink. This harvesting process basically destroys the bog at a far faster rate than the peat can be formed, and is not sustainable. As a result, we have lost something like 94% of our peat bogs in northern Europe over the last half century. Peat use for potting compost is a relatively recent phenomenon, in the last 50 years or so, before that we relied on loam-and-leafmould blends. In addition to commercial extraction, many bogs have been drained for agricultural purposes. Climate change is also having an effect on bogs, and it is thought that there has been a slow-down in peat formation over the last few thousand years. Do we have the right to destroy the few remaining areas of bog habitat? Personally, I don't think so, and society in general is forming the view that the use of peat is morally unacceptable. Over the last year or two many members have reported difficulties in finding supplies of moss peat, which is due to a reluctance of many garden centres to stock the product?.so we need to look for alternatives. There is a real chance that peat will not be freely available in years to come.

The Carnivorous Plant Society is dedicated to the conservation of carnivorous plants, which implies their habitats as well, and so the society as a whole, and individual members, have a responsibility to play their part in the conservation of peat bogs.

I have not bought any peat for nearly ten years now. Well, not strictly true, but near enough. There was an episode a few years ago where my regular supplies of peat-free composts dried up and I had to grit my teeth and buy some Sphagnum moss peat. I do not think anyone who has come to my open days or swapped plants will deny that my plants are as healthy as anyone else's, and one of my Sarracenias won the "tallest pitcher competition" on the CPUK Internet forum last summer, so peat is not essential for growing CP's. So what are the alternatives? Well here is a selection of some composts that I use or have used in the past:

Cocopeat

Cocopeat is manufactured in the tropics, centred around Malaysia, and is a by-product of coconut production. The husks of the coconuts are composted and milled to produce a substance very similar to peat in structure and water holding capabilities. Cocopeat was my first choice for an alternative compost when I first started looking. At the time, Wessex produced large bags of coir compost and most garden centres stocked this, but it is not as available these days. The results from using cocopeat were not ideal. I felt that it contained more nutrients than peat and it also broke down more quickly. Additionally, it did not support the growth of Sphagnum moss. I found it an acceptable compost for certain plants, mainly mature plants of Sarracenia,Dionaea, Nepenthes & Pinguicula. Seedlings, and many of my Utricularias and smaller Droseras, did not do very well in the compost. Cocopeat has been superseded I believe by other composts, but if it is the only compost you can get then give it a go, especially for those plants which are less fussy about their composts such as Nepenthes and Pinguicula. Bear in mind that I did keep my entire collection going on cocopeat for several years!
 
It is mainly available mail-order (in a dried, compressed state which needs re-hydrating) from various companies including The Organic Gardening Catalogue (see below). Don?t buy the version with added fertiliser!

Moorland Gold

This is my current compost of choice. It is peat alternative derived from the filtering of water from the hills in west Yorkshire before it enters the drinking system. Natural erosion from the peat moors deposits large quantities of peat, silt and leaf mould in reservoirs, which are then dredged out and the compost packaged up. Moorland Gold is an alternative to mined peat, but it does contain particles of peat. However, this peat is not the result of the destruction of peat bogs and is arguably a sustainable resource. The suppliers, West Riding Organics, maintain that there are at least 50 years of supplies currently in the reservoirs. Because this product is derived from peat moors, the properties are very similar to that of peat (acid reaction [pH 5] and low conductivity [0.7 micro-siemens]) and gives similar results. It is very dark in colour, nearly black, darker than Sphagnum peat which tends to be more brown. It is also a bit heavier than peat, due to the silt content, so I tend to add a bit more perlite to mixes to lighten them up a bit. Disadvantages? It does produce quite a lot of grass and heather weeds in pots, but not a major disadvantage I think.

Stockists:

Until recently, it is also been quite difficult to obtain. I get my supplies from my local organic farm shop, and you can always try approaching your local shop and asking them to stock it. The price is around £2.50 upwards for a 45 litre bag. You can now buy it mail-order, but bear in mind that it is quite heavy and you will pay a lot of postage.
A couple of mail-order suppliers are:

Tamar Organics,
Tavistock Woodlands Estate,
Gulworthy, Tavistock,
Devon, PL19 8DE
Tel: 01822 834887
Fax: 01822 834284
Web: http://www.tamarorganics.co.uk
£3.95 per bag, but £9.95 including postage mail-order (plus an additional 75p postage for orders under £15)

The Organic Gardening Catalogue,
Riverdene Business Park,
Molesey Road,
Hersham, Surrey,
KT12 4RG
Tel: 0845 130 1304
Fax: 01932 252707
Web: http://www.organiccatalog.com
£9.25 per bag mail-order including postage (plus an additional £1 postage for orders under £20)

If you want to buy it on a bigger scale, contact the producers directly:

West Riding Organics,
147 Brights Buildings,
New Mill Road, Honley,
Huddersfield,
HD7 2QE
E-mail: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Web: http://www.organics.uk.com
Tel: 01484 609171 or 01484 661956
They will sell you from 20 bags upwards for £1.85 each plus £30 per load for delivery.
Very worth getting together with some friends and ordering a load!

Sphagnum moss:

This can be used fresh (live) or dried; dried moss needs to be re-hydrated. Many growers have Sphagnum growing as a topdressing on the tops of their plant pots, particularly with species such as Darlingtonia and Heliamphora, and you can simply pull off pieces and stick them into the tops of other pots where they will grow.

Although I don't use pure Sphagnum as a growing medium for many plants, (apart from certain epiphytic Utricularias such as U. humboldtii & U.nelumbifolia ) it can be used for almost any carnivorous plant, and some growers use it extensively. Live Sphagnum will continue growing and swamp seedlings and small-growing species, so consider dried or Supersphag instead for these.

Stockists:

Grow your own! Also available fresh from certain garden centres as "hanging basket moss", although do check that it is Sphagnum moss, as other moss species are sometimes sold. Do not collect it from the wild without written permission, and bear in mind that any bogs with Sphagnum growing on them are probably protected as nature reserves and collection from there will be illegal.

Also available dried from many mail-order sources such as:
Hampshire Carnivores,
Ya Mayla, Allington Lane,
West End, Southampton,
SO30 3HQ
Tel: 023 80 473314
Mobile: 07703 258296
Fax: 023 80 473314
E-mail: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Web: http://www.hampshire-carnivorous-plants.co.ukhttp://www.hampshire-carnivorous-plants.co.uk
150 g bale makes 7.5 litres £3.90 each, 500 g bale makes 22 litres £9.80 each, 1 Kilo bale £19.00 each

There are other CP growers that also sell Sphagnum moss

Supersphag:

Supersphag is a by-product from the New Zealand Sphagnum industry. It is not milled Sphagnum but is the tips of the growing points that inevitably drop from the harvested moss while it is being dried on huge racks. Supersphag is sold in compressed blocks that rapidly re-hydrate when added to water. Four blocks will re-hydrate to make a litre of moss. In use it forms a medium textured growing media, more compact than regular Sphagnum moss but more aerated than peat composts. It is ideal for the vast majority of carnivorous plants. The re-hydrated moss is resistant to decomposition and so maintains its open structure for a long time without rotting.

The moss also does not re-grow. This makes it ideal for small growing plants and especially seedlings, without the problem of being swamped by mossy growth that is an ever present factor with regular moss mixes. It is an entirely renewable resource and so is an ideal substitute for peat based composts. The moss is only harvested from environmentally controlled sites and the Sphagnum is allowed to regrow fully before harvesting again.

I find Supersphag good for Nepenthes, Heliamphora & Genlisea, but have not tried it with many other species due to the cost, although I suspect most plants could be grown in it. I tend to mix it with equal parts perlite when I use it, to stop it becoming too compacted. Also excellent for taking leaf and root cuttings. Phil Wilson recommends it for difficult-to-grow Droseras, and I have certainly had better results with Drosera regia, D. cuneifolia & the D. villosa complex with Supersphag than I have with other composts. I have also found it excellent for Joseph Clemens' infamous "wet" propagation method for Drosera regia root cuttings. As it does not break down quickly, the product can be used several times over if required, just rinse and re-pot!

Stockists:

Phil Wilson,
14 Rope Walk,
Martock,
Somerset,
TR12 6HZ.
E-mail: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
20 blocks (sufficient for 5 litres compost) £3.50 plus £1 postage

THRIVE:
Thrive is a commercial peat-free blended growing media "...specifically developed for carnivorous plants. The result of several years of research, development and commercial trialling...." The exact mix is a commercial secret, but from closely examining the blend I have it contains perlite, sand and what I am guessing is ground & composted pine-bark, but there may be other ingredients as well. The producer claims that independent trials have shown conclusive evidence that those grown in Thrive gave better results than others grown side-by-side in a regular peat/sand mix. The Irish Peatland Conservation Council have apparently just planted up their entire C.P. display in 4800 litres of Thrive.

The mix I have is an older blend designed specifically for Sarracenia, and I am guessing that the current formulations are a similar mix. They offer a "multi-purpose" mix for most genera of carnivorous plants, complimented by two bespoke products for Monkey Cups and Butterworts, in sizes from 60 litres downwards. I have had 2 mature Sarracenia planted in Thrive for a couple of seasons now, they are doing well and I cannot tell any difference in growth between them and others grown in different composts. One of the pots has maintained Sphagnum growing on the surface which impressed me, the compost is obviously acid and low nutrient although I do not have any exact figures.

Stockists:

::The Prices above are dated at September 2004::

The above article was printed in September 2004 CPS News