Climate-friendly peat-free composts aren’t taking their place at the heart of more eco-savvy gardening because we’re not yet paying enough for them.
By John Walker. Published in Kitchen Garden, November 2010.
When well-known gardening pundits start proclaiming just how ‘awful’ it is that children should get their fingers dirty when using ‘filthy’ potting compost, you know that something’s going seriously wrong in the world of compost manufacturing. Like many gardeners who temporarily suspended their incredulity at the revelation that compost makes your hands dirty, I pondered, though only for a millisecond, whether a non-hand-dirtying potting mix might exist. Alas, no one has yet cut open a bag of ‘clean’ potting compost, and if there’s any sanity left in the world, we never will.
To improve peat-free compost’s earth-friendly credentials we need to dig deeper into our pockets and start paying more for it – and not fret so much about finding a few ‘bits’.
The only clue you need as to why this bizarre claim arose is that the said compost was a peat-free mixture that, in one school garden, had given comparatively poor results. To add to the ‘awfulness’, our pundit laments how they picked thorny twigs and bits of glass from other peat-reduced compost mixes, and how this terrifying combo of alien fragments and dirty hands would scare children away from ever gardening again. Their ‘solution’, of course, is to only use peat-based seed and potting composts, even though digging up peat, a ‘fossil’ source of carbon dioxide, contributes directly to global warming and destroys wildlife-rich peatland habitats. You can imagine the classroom confusion: the gardening expert is telling the teachers to use peat compost (presumably to save on hand-washing), while the science teachers are explaining to their pupils how using peat is helping to worsen climate change…
This is just one example of how low some gardening commentators will stoop in order to denigrate any compost mixture that’s not pumped full of peat. The peat industry is long past its ecological sell-by date, but that isn’t going to deter the virulent pro-peat pundits from using every trick in the book to keep us hooked until they’ve flogged their last bag of the stuff.
It’s also just one symptom of a crisis now unfolding at the heart of the compost-making industry. But this is no single-issue crisis; its roots are deep, and spreading. Its key, intertwined components are, in no particular order: ignorance and confusion, lack of information, deliberate disinformation, spin, ‘cheap as chips’ expectations, selfishness, limp gardening journalism – and much turning of a blind eye to scientific reality.
Let’s get the ‘scientific’ bit straight. When you dig up peat, a non-renewable ‘fossil’ substance on a par with coal, oil and natural gas, to make compost, it dries out and the carbon it previously stored safely in the ground is released as carbon dioxide, the main ‘greenhouse gas’ driving global climate change. Mining peat also destroys wetland ecosystems which, if left undisturbed, actually absorb and lock away carbon from the air – they’re some of Earth’s most important carbon ‘sinks’.
As it rots down, the material that goes into my compost bin-cum-wormery (which would otherwise go to make peat-free compost or soil conditioner) releases only the carbon it absorbed when the plants were growing.
In contrast, making peat-free compost from ‘green waste’ (collected via household wheelie bins) diverts organic materials – anything from old brassica stalks to lawn mowings – from going to the ‘tip’ and then to a landfill site, where they get buried in the ground. There, in the compressed, compacted and airless conditions, they rot down and produce methane, another greenhouse gas, but one 25 times more potent than carbon dioxide. So by making compost primarily from plant remains, we’re both removing the need to use climate-changing peat and avoiding methane gas production.
It’s true that when plants rot down, either in your compost bin or in those big, steaming windrows you see on the edge of town, they release much of the carbon they stored while they were growing. But they only release what they absorbed from the air in the first place; when we dig up peat we’re actually adding extra carbon to the atmosphere that was previously stored away in ‘fossil’ form (plus any arising from processing, bagging, transporting and selling it). Making peat-free compost isn’t drawback-free. Energy is still burned to gather the raw materials, to turn the heaps, and then to transport the finished product, but if the composting process takes place close to where the raw materials are sourced, its overall ‘carbon footprint’ starts to look a whole lot lighter than that of peat-based composts.
So what about the fragments of glass, twigs and other bits and bobs that inevitably do appear in bags of peat-free from time to time? When you’re collecting green waste on a vast scale some contamination is unavoidable, and some ‘bits’ are inevitably going to outwit even the most rigorous screening process. Peat-based composts do tend to be free of unwanted detritus, but the real test is whether our awareness of the ecological consequences of using peat can be trumped by the irritation of finding a few ‘bits’ when we open a bag of peat-free. A few ‘bits’ (bar glass, which is a no-no in anyone’s book) are, surely, a small price to pay for climate-friendly compost?
We rarely hear any good news about peat-free composts, yet these lettuces are all growing well in peat-free composts. GCL is my own mix of 50:50 garden compost and leafmould (for more information click on the picture).
The perceived underperformance of peat-free composts is another line of attack favoured by the pro-peat brigade. Unfortunately, peat-free compost is subject to a phenomenon afflicting all aspects of life: you rarely hear good news. The letters pages of gardening magazines seemingly abound with horror stories of how terrible peat-free and peat-reduced composts are; it’d be a rare reader who would take the trouble to put pen to paper to sing the praises of peat-free (although Which? Gardening did award ‘best buys’ to three peat-free container composts earlier this year).
Even gardening journalists are happy to jump on the peat-free-bashing bandwagon. One editor recently announced how they would rather not play Russian roulette with their plants, and would be sticking with peat-based compost because they couldn’t watch their plants die. Gardening success, it seems, must come at any cost – even if it means playing Russian roulette with the climate itself.
But the chief driver of our compost crisis is us; we just don’t pay enough for the stuff. For many years all we’ve seen and heard is ‘buy two, get one free’ or ‘three bags for a tenner’. Our resulting mindset, ably massaged by a profit-hungry gardening industry, has forced the manufacturers of peat-free compost to get it down to a rock-bottom price, ‘cheap as chips’. Is it any wonder that some gardeners get less than perfect results with peat-free when all they’re spending on it is a few quid? Nurserymen who use peat-free compost pay considerably more for a superior, reliable product, to ensure that they stay in business. It’s about time we did, too, not only to ensure that our food-mile-cutting kitchen garden crops succeed, but also to avoid the climate chaos that’s already afflicting crops in distant plots, less pampered than ours.
“The chief driver of our compost crisis is us; we just don’t pay enough for the stuff”
Our compost crisis isn’t going to be remedied by some silver bullet fired into the heart of the compost-making industry. As earth-friendly gardeners we can do our bit to give climate-friendly compost a leg up, by being ready to pay a realistic price for top-quality peat-free mixes that are consistent, reliable and – hopefully – free of ‘bits’.
It might come as a jolt when the barcode’s scanned at the checkout, but the peat-free bleep will be as nothing compared to the ecological alarm bells set ringing by scanning a bag of peat-based multipurpose.
I do so agree, but have recently used peat as a result of trying to find a suitable compost.The problem I found with green waste compost was that there seemed to be traces of aminopyralid symptoms .I and others have found aphid and other pests proliferating in green waste compost. As councils cut back on bin collections to encourage recycling, so more treated , weedkiller contaminated waste gets dumped in the green waste. The same problem arises using stable manure and finding the straw has been treated so your home made compost poisons crops. We are now trying to make our own compost by using peastraw for the stable and mucking out into a cart, then turn once, then into deep beds in the polytunnel with soil on top as a biofilter. Plastic on top while it cooks heats germinating seedlings in trays, then in go crops.The co2 and nitrates stay in the poly and increase growth.It heats the poly too.
If we were to do this for sewage , we could heat homes and produce a fertiliser as a byproduct. Instead we throw away what we consider to be waste .