Transition Culture

24 May 2006

An Evening in Peter Harper’s Garden.

**Peter Harper** has been at the Centre for Alternative Technology for over 15 years as a landscape designer, director of biological research and now as Head of Research and Innovation. He is author of many articles and of the classic “Natural Garden Book”, which I think is now tragically out of print. He lives in Machynlleth has done a great job of renovating his traditional cottage as ‘greenly’ as possible, as well as creating a beautiful and productive garden.

Peter is great at testing green claims using research, trying out old wives tales and the more optimistic claims of permaculture and organics to see if they actually work. He is a great one for measuring, weighing, recording and estimating. He did a great study that was published in Permaculture Magazine where he pruned an old apple tree in his back garden, weighed all the bits, and extrapolated that if the back garden were full of such trees how much a family could save on an annual basis in terms of fuel. He compared this with natural gas, and concluded that it would produce a saving to the family of £3 per year! His point was the growing fuel on a domestic scale is not a cost effective use of space.

The last time I saw Peter was at the 1995 Permaculture Convergence, where he gave a wonderful slide show about nitrogen’s role in accelerating the composting process. He gave a glorious slide show where he illustrated experiments he had done where he peed onto books over a period of months, photographing the process of decomposition over that time. After one month you could see orange moulds moving in, after two months other even more psychedelic moulds had moved, and eventually they were reduced to compost. This was the session just before lunch, and I still tell students on permaculture courses about his presentation, it was a great combination of humour, scientific rigour and shock value!

Peter’s house has a number of great ‘green’ features. His place is the base for a neighbourhood car sharing scheme. They run 3 cars, all run on biodiesel, which requires no membership fee and people pay 30p a mile to use it. He also has a very innovative grey water recycling scheme. His upstairs bathroom has a urine separating toilet, and the urine and the bathroom grey water (not the kitchen sink grey water, because it contains too much fat) the combination of which he calls “house juice� is sent through a straw filter and into a tank (see left). From here it is used in the garden for a range of things.

It is used as a trickle feed for a number of things, a line of soft fruit, veggie beds and one of his experimental projects, the composting path. This is a lovely application of the permaculture principle ‘everything gardens’. Here, he has laid twiggy materials and clippings from a privet hedge along a path, with a hosepipe perforated in some places and not in others, and all covered with an old carpet. The idea is that as people walk up and down the path they crush the twigs and break them down, and the fact that some areas receive the ‘house juice’ and others don’t allows him to see if it speeds decomposition at all. Genius.

The garden is also full of experiments into the use of different forms of compost as a growing medium, a mixture of annual and perennial crops and other things besides. At the end of the garden is a variety of compost bins. Peter takes compostable stuff in from his neighbours and composts it, they can have some of the resultant compost if they want. He uses a variety of methods and is always trying out new ones, and is only too happy to share the results (see left…).

One of the most interesting he calls the Soil Stack Compost system. This is like a big tower into which he puts everything, sods of turf, weeds, twiggy stuff, all sorts. These then slowly settle and break down, and the bin is open at the bottom, so any compost falls to the bottom where it can be removed. Any twigs that fall down can just be tossed back in the top again. He had also been experimenting with supposedly ‘compostable’ disposable nappies, with little success.

Peter’s garden is a great example of both a productive back garden and an investigative mind, always challenging orthodoxies and seeking what actually can be shown to work. It was also a gorgeous place to spend a sunny Sunday evening, listening to the birds and to the experience and insights of a true natural gardening pioneer.