“I think few people know at 18 what they want to do in life,” muses Martin Crawford. He had chosen to study maths and computer science at university, and saw himself entering the fast-moving world of IT. His thirst for innovation, however, was to take a radically different direction. Always an outdoor person, he began to take an interest in horticulture and to volunteer at small, organic farms at weekends. By the time he graduated, he was fairly sure he wanted to spend his life among plants. A year working in computing confirmed his decision, and he spent the next four years moving from job to job, in Britain and France, working (many mainly unpaid) in organic market gardens. At one point he could be found on the Scottish island of Iona, where the winds lashing in from the Atlantic were so fierce he had to stake his young cabbages and courgettes to stop them blowing away. After that, restoring a walled garden in Devon was bliss. He loved the intimacy of the landscape, and when he was ready to set up his own market garden, he chose to do so in south Devon, selling his produce through the market at Totnes.
It was a happy life, recalls Martin, if a hard one. “But after a couple of years I began to have doubts about how sustainable it was. So I started researching about soil (there were concerns even 25 years ago) and about carbon emissions and climate change, which was definitely fringe at that point, and began looking into agroforestry – integrating trees with crops. There was a man called Robert Hart who had been writing pamphlets about the experiments he was doing in his garden in Shropshire. He called it ‘forest gardening’. I went to have a look, and found it quite inspiring, even though he freely admitted that he didn’t know that much about what he was doing. But even so, he had created a very interesting system. And I saw at once how I could take his ideas forward.”
Hart’s experimental forest gardening growing system had, for him, been something of a hobby. Martin wanted to investigate forest gardening properly, to establish, through methodical research and experimentation, a sound, scientific basis for forest gardening, by which he meant a low-input, multi-layered cropping system, modelled on young, natural woodland. So in 1992 he set up a charity, the Agroforestry Research Trust, and approached the Dartington Hall Trust for some land. By 1994, he had a two-acre field, and began to plant his first demonstration garden. Three years later, Dartington leased him a further eight and a half acres, now used as trial ground for fruit and nut crops. He acquired a further site in 2011, where he established two small-scale forest gardens as templates for domestic gardens. He is also developing a greenhouse garden, working out what we can grow if mean temperatures, as predicted, rise by 5°C.
Forest gardening is standard practice in the tropics, where gardens mimic the rainforest in assembling layers of productive planting beneath the canopy of tall trees. In the lower light levels of northern Europe, Martin explains, forest gardens more closely resemble the more open woodland edge, with a top layer of larger fruit trees, often hung with vines and climbers, a lower layer of smaller fruit and nut trees, and an understorey of bamboos and berry-bearing shrubs. Below come perennial vegetables, while mats of herbs and sprawlers cover the ground. Not all the plants are cropped in a forest garden – some encourage beneficial insects, others aid fertility by fixing nitrogen or ‘mining’ trace elements deep in the soil.
It’s not a quick option – Martin’s forest garden in Dartington took ten years to establish. And although plants are largely left to their own devices, no garden is entirely maintenance-free. Our best-loved vegetables are largely sun-loving annuals, but forest gardening requires shade-tolerant perennials, some already familiar to us as ornamentals, such as hostas, columbines and Solomon’s seal. Orangutans, Martin points out, eat around 400 different types of leaf and fruit; modern European humans will be hard pressed to get above 40. He has more than 500 different plants in the Dartington forest garden, and has tested every edible to ensure it is not just safe, but actually pleasant to eat.
It is climate change that drives him. “All our growing systems should be storing carbon; plants and soil are currently the only way of taking carbon out of the air. No-till agriculture will help a bit, or even scattering a few trees through a grassy field. But forest gardens are the system that stores most carbon while yielding lots of crops.”
In the wartime Dig for Victory campaign, individual households used their private patch both to feed themselves and to contribute to the common good. Forest gardens, he believes, could do much the same. “I can’t solve the world’s problems. I’m not a protestor – I’d rather put my energy into practical stuff. But I do believe in the ripple effect. If I can be the stone that makes a few ripples, and those ideas spread out, that’s as much as I can do.”
Useful information The Agroforestry Research Trust provides tours, courses and books on forest gardening, visit agroforestry.co.uk