Hartley Magazine

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Considerate cultivation: running your garden on renewable fuels

Going peat-free is essential in an earth-friendly garden, but there’s more: the compost you use needs to be a truly renewable fuel.

Coaxing a steep, bracken-riddled bank of acidic, nutrient-poor soil into a structured, productive garden might sound challenging enough. But imagine setting out to do it in a deliberate, thoughtful way where your guiding tenet is that its creation and care should – as far as is humanly possible – have no negative knock-on effects on the world around you. This is the nub of what ‘earth-friendly’ gardening means to me: considerate cultivation which does more good than harm, gives more than it takes, enriches rather than depletes – and delivers limitless enjoyment. But I’ll confess that I played fast and loose with some of these sentiments while entangled in bracken rhizomes or when hauling reclaimed slate up a rain-sodden slope, and that sometimes I’ve been cornered into making some rather earth-unfriendly choices.

Probably the single most important choice we make in our gardens and allotments, which defines our degree of earth-friendliness, is the kind of ‘fuel’ we use to power up our plots. Before the arrival of my lean-to greenhouse, most of my fuel came straight from the sky as non-polluting, ‘green’ and renewable modern sunshine. It still does, but now I catch it under glass and make it work even harder. But greenhouses change things. They create a different kind of gardening space that tempts us to try new things and to grow plants which can’t cut it outdoors. They bring spring on earlier, fend off the onset of autumn, and soften winter’s bite. They deliver endless possibilities for raising and multiplying plants we’ll never find in garden centres. They move gardening into top gear.

My home-grown peat-free mixture of 50:50 garden compost and leaf mould (GCL, on the left) is not only the most ‘earth-friendly’ fuel for filling my pots and trays, it also outperforms other ‘imported’ peat-free composts. To see more results with sweetcorn (and other crops) in my compost trial, click the image.

When it comes to raising plants from seeds, plugs, bulbs, tubers, cuttings – however you do it – there’s a second kind of fuel you need to make the whole wonderful process possible: seed, potting or ‘multipurpose’ compost. This fuel doesn’t come freely from the heavens above; it arrives in barcoded plastic bags. We use compost to start seeds into life, to give seedlings room to grow, to pot up plugs, to root cuttings, to plant bulbs, to fill patio tubs, window-boxes and hanging baskets, and to give resident greenhouse plants the root-room they need to be productive. Without compost our gardening wheels don’t just squeak, they stop turning.

One of the most interesting roles my garden plays is that of a testing ground, be it for new plant varieties or for products with promising eco-worth, including compost. I’m putting around two dozen ‘peat-free’ composts, mostly ‘multipurpose’ types (designed for sowing, potting up young plants and filling large containers), through their gardening paces by using them to grow various plants, from tomatoes to winter-flowering pansies. Peat-free composts are those made from materials other than sphagnum moss peat or (on a smaller scale) sedge peat. The ones I’m trialling contain various materials, including bracken, sheep’s wool/manure, coir (coconut fibres), coir and charcoal (biochar) mixtures, ‘green’ upland peat recovered from water filtration systems, green waste compost (made from the stuff we put in brown wheelie bins), composted bark, wood fibres, and my own 50:50 combo of lovingly-sieved three-year-old leaf mould plus garden compost taken from my ‘cool and easy’ – that is, slowly rotted, worm-worked and unturned – compost bins.

I’ve been gardening in peatless splendour for years, but then something started to bug me: over and over I keep hearing and reading – and being told – that ‘peat-free compost is rubbish’ (not all descriptions are quite so tame). This damning verdict comes with no qualification, not so much as ‘some peat-free composts…’. And, it must be said, this charge usually comes from gardeners and media gardening pundits who see no problem with continuing to use peat – a finite, non-renewable natural resource. It’s been the fuel of choice for gardening for decades, so when upstart peat-free ‘alternative’ fuels came along, some with increasingly green credentials, it’s little wonder that some have been reluctant to try them in their garden or allotment ‘fuel tanks’.

If putting peat-frees through their paces has shown me one thing, it’s that the ‘rubbish’ claim is only part right. Yes, there are some peat-free composts being sold that are not fit for gardening, but there are others that’ll give any peat compost a run for its money – and with a lower environmental cost.

But another thing bugged me, even with peat-free compost: whatever it’s made from, it’s effectively being ‘imported’ into my garden. Even though bags of peat-free don’t carry the burden of driving the destruction of natural habitats (lowland raised peat bogs) and their biodiversity, along with any archaeological records they contain, or exacerbating climate change through the release of carbon dioxide (which undamaged healthy bogs soak up and store away), their journey to my greenhouse isn’t ecologically cost-free. Processing, packaging, transportation and marketing all take their toll on any ‘green’ product’s greenness, whether it’s compost or anything else.

All my kitchen and garden waste goes into dalek-style recycled plastic compost bins where it rots down slowly – aided by compost worms – into dark and crumbly ‘fuel’ that helps make my garden grow. Removing the bin reveals the different stages of breakdown: fresh material at the top, ready-to-use fuel at the bottom.

There’s one compost in my trial that didn’t arrive via car boot or white van, needed no processing (other than sieving and mixing), required zero packaging, and didn’t need marketing. Its journey to my potting bench, by huff- and puff-powered wheelbarrow, was all of 40m (44yd). It didn’t dent any natural habitats, cause a drop of climate-altering ‘fossil fuel’ to be burned, leave me with empty bags, or cost me a penny. It also happened to germinate seeds and grow strong, healthy plants to rival those produced by any of the best peat-frees available. My home-made mixture of half leaf mould and half garden compost might sprout a few harmless weed seedlings, but in terms of sheer earth-friendliness, that’s a minor hiccup that won’t stop me giving it top marks.

For gardening to become renewable – in the sense that we can keep on doing it and enjoying it without further depleting natural and non-renewable resources – we need to find ways to power our gardens and greenhouses with fuels that can be renewed on a regular basis. We’re off to a cracking start with modern sunshine, but unless we choose more environmentally-sound versions of that other garden-making fuel, compost, our gardens will continue to take more than they give, and to deplete rather than enrich the world around us.

Click here to visit my gardening trial of peat-free composts.

Text and images Β© John Walker