Working with nature to grow edible Crops
Creating a Forest Garden
by Martin Crawford
Green Books
Hardback 384 pp
Forward by Rob Hopkins
Martin Crawford, Director of the Agroforestry Research Trust in Devon, UK, has produced a beautiful and practical book which seems sure to become the definitive text for cool temperate forest gardens.
As part of his work at the ART Martin is already the author of many encyclopedic manuals covering dozens of topics and thousands of plants, and has been producing the essential Agroforestry News since he began his forest garden in the Dartington estate 15 years ago.
Creating a Forest Garden is eminently practical and down-to-earth, packed with information and good advice, and illustrated throughout with really gorgeous colour photos, including many full-page ones making it of interest to the general lover of plants and gardens as well as the serious forest garden designer. As such it succeeds in bringing together the technical issues of forest garden design, comprehensive details on edible and useful plants as well as introducing the concept to the non-specialist.
Above: Martin engulfed by bamboo with Italian Alder growing behind him at his garden at the ART
The concept of edible “food forests” – combining tree crops such as top fruit and nuts with various understory layers such as small and large shrubs, perennial vegetables, ground-covers, herbs and climbers – expresses many of the principles of permaculture: multiple function; stacking different layers; diversity and use of biological functions such as nitrogen fixing plants.
The book is clearly laid out into three sections:
Part 1 How Forest Gardens Work
This section introduces the reader to the concept of forest gardens and how they evolved in British climates from the work of Robert Hart. There follows a survey of forest garden features and products. Martin then gives a fascinating look at the effects of climate change on the UK climate and the relevance of forest gardens to landscapes resilient to these changes;
The section ends with a brief discussion on the “native – exotic” debate – Martin points out that many definitions of what constitutes a “native plant” are in fact arbitrary:
…plants introduced by other animals to a new area are “allowed” as native but those introduced by humans (deliberately or not) are not. This is an example of the all-too-common attitude of the last few centuries, of humans being separated off from the natural world as though they are not a part of it. Just look where that has lead us!
This is an important issue to forest gardeners – as Martin points out, the range of “native” wild edibles is quite small in this part of the world; productive forest gardens here will need to introduce many plants, but it should be remembered that few of our food corps – much less ornamental shrubs – are actually “native” anyway.
This section ends with a detailed look at fertility in forest gardens. Martin shows how to make an assessment of the nutrient demands of your plants and average this out over the area you have, and then how to calculate how to meet this demand from nitrogen fixing plants and mineral accumulators like comfrey.
This key idea in forest gardens of achieving a high degree of self-maintenance is one of the great strengths of Martin’s approach. Unlike conventional annual veg growing, which tends to rely on inputs of manures for fertility, a forest garden would ideally cycle its own nutrients as far as possible and limit any extra inputs.
Part 2 Designing Your Forest Garden
This section explains the other major aspect of the self-maintaining nature of edible forest gardens – they should have perennial or evergreen groundcovers to minimize weeds.
The key to this is how to establish useful ground covers that you want in the first place. In the book Martin shows how to first eliminate the existing vegetation with plastic or cardboard mulches, which should be down for a year before removing and then planting the area with suitable beneficial ground cover plants. In my experience this is the aspect of forest gardening that is most commonly neglected or poorly implemented – people’s initial interest tends to draw them to the trees and shrubs, but in many ways it seems to me that it is the perennial vegetable and ground cover layers that really define it as such – rather than an orchard with grass that needs mowing, and this takes careful preparation and selection of species.
The chapter on growing your own plants will be essential to most gardeners – the number of ground cover plants needed to fill a space quickly and keep those weeds down can be considerable and beyond most people’s budget. Martin takes you through the main propagation techniques for a range of plants including grafting trees and shrubs.
Chapters 9 and 10 take the reader from first design steps – starting with the selection of a suitable site if one is the market for buying land – and the important aspect of wind-break design.
Then follows a series of chapters for designing each in turn the canopy layer; the shrub layer; the herbaceous perennial and ground-cover layers; and annuals, biennials and climbers, with a chapter for each with comprehensive plant lists that make for hours of happy browsing and nearly justify the book purchase on their own
Part 3 Extra Design Elements and Maintenance
The final section covers the landscape features of paths and clearings and how design them into your forest garden for maximum light.
This followed by a chapters on:
- one of the most fascinating potential yields that can be added into a forest garden – edible fungi and how to grow them on logs or sawdust;
- harvesting and preserving – tips on what to do once you have an abundance of yields;
- maintenance, including weeding (which is essential but should take minimal time in a forest garden) and pest control
- ongoing tasks.
Four useful glossaries are found at the back of the book: Propagation tables, trees and shrubs for hedging and fencing, plants to attract beneficial insects, and edible crops by month of use.
Resources – useful organizations, suppliers and publications – complete the book
There is very little I could suggest to improve this comprehensive book. I would have liked to see a couple of references to research in places – for example in the first chapter he states “there is plenty of evidence that crops from perennial plants tend to be more nutritious than similar plants from annual plants” – it would be interesting to have some references to follow up.
My visit to Martin’s 2-acre forest garden in 2008 was an inspiration, reinvigorating my interest in the potential of the concept, and showing how multiple yields can be obtained efficiently with relatively little maintenance required.
While there is still little data to demonstrate to what extent forest gardens can really feed people in this part of the world – Martin does not claim they can or should completely replace annual vegetable gardens or conventional farming – this wonderful book is another demonstration of how the edible forest garden concept can successfully integrate productive food gardens with diverse habitats, and provide many other ecological and aesthetic qualities. It is sure to inspire many more new forest gardens and gardeners over the coming years.
