How to Grow Perennial Vegetables

Low-maintenance, low-impact vegetable gardening

Martin Crawford

• Publisher: Green Books
• Year: 2012
• Print ISBN: 9781900322843
• eBook ISBN: 9780857840943
• Topic: Biological Sciences
• Subtopic: Horticulture
• Index: Biological Sciences

Perennial vegetables are a joy to grow and require a lot less time and effort than annuals. In this book Martin Crawford gives comprehensive advice on all types of perennial vegetable (edible plants that live longer than three years), from ground-cover plants and coppiced trees to plants for bog gardens and edible woodland plants. There are many advantages to growing perennial vegetables, for example: * they need less tillage than conventional vegetables and so help retain carbon in the soil * the soil structure is not disturbed in their cultivation * they extend the harvesting season, especially in early spring * and, of course, they are much less work. Part One looks at why and how to grow these crops, and how to look after them for maximum health. Part Two features over 100 perennial edibles in detail, both common and unusual - from rhubarb to skirret; Jerusalem artichoke to nodding onions. This book offers inspiration and information for all gardeners, whether experienced or beginner, and also includes plenty of cooking tips. It includes beautiful colour photographs and illustrations throughout.

Part 1

An introduction
to perennial
vegetables

Chapter 1

Why grow perennial vegetables?

Most gardeners who want to grow some of their own food have a combination of annual vegetables and fruit bushes and/or trees, but few have perennial vegetables (apart from, perhaps, rhubarb). This seems such a shame, because there are some fantastic food plants out there with delicious flavours that are often very easy to grow.

Oca is a crop widely grown in the Andes, with delicious lemon-flavoured tubers.

What is a perennial vegetable?

For the purposes of this book, a perennial vegetable is defined as a plant that lives for at least three years, and is raised for some edible part of it – such as the leaves, shoots, leaf stems, roots or flowers. The edible part might be used raw or cooked. The plant must also be capable of being harvested without killing the plant itself. You’ll also find some well-known fruiting plants included here as a vegetable – strawberries, for example. These are included only if a part other than the fruit can also be eaten.

There is a distinction, rather blurry, between a vegetable and a herb. A herb (in the culinary sense) is a plant with a strong, distinctive taste, used as a flavouring in relatively small amounts. So I have not included, say, lovage as a perennial vegetable, even though it is perennial, and is edible. However, I do include some plants that we often think of as herbs if they can be used in bulk amounts in salads or cooked dishes – so you will find entries for some of the mints, and for sweet cicely.

In the context of this book, I am talking about plants being perennials in the climatic conditions found in the temperate and continental climates of Europe and North America. Some annuals of course become perennials if the climate is warm enough, and these are not usually included unless, like runner beans, they can be grown as a replant perennial (i.e. a plant that is perennial in a warm climate but in a cold climate can still be grown by lifting plant parts in autumn, storing them over winter and replanting in spring).

Also in this book are some replant perennials such as potatoes and mashua, where it is common practice to save some of the tubers in the autumn for replanting next year.

The case for growing perennials

There are lots of reasons why growing perennial vegetables makes sense.

Less work

You don’t have to cultivate the soil every year. Turning the soil over takes a lot of energy, whether it is tractor energy in ploughing or human energy in digging. Because perennials are planted only once (or once every few years), you do not have to disturb the soil so often.

If you stop turning the soil, and keep on top of the flush of weeds you’ll get from the initial soil preparation, then the weed seed bank in the top layer of the soil will not get replenished with deeper dormant seeds. You’ll find that the weeding required decreases over time, especially if you mulch around your perennials.

Because most perennials do not need digging up every year, it is more important to weed out pestiferous perennial weeds when small. (When growing annual crops, the weeds can always be dug out in winter.) Nevertheless, even in the first year after planting, the weeding demanded should not be any greater than that for an annual crop.

Fewer carbon emissions

A few years ago, nobody considered what carbon emissions were resulting from agriculture and horticulture, but that is changing rapidly. Growing food and other materials creates a lot of carbon in the atmosphere, not least because almost all crops are short-lived, requiring the energy-intensive cultivating of soil every year. Cultivating the soil exposes soil organic matter (humus) to air both on the soil surface and in the soil itself, leading to release of carbon in the form of carbon dioxide.

Once you stop digging soil, carbon emissions are vastly reduced, and quite possibly reversed – you may start to actually store more carbon in the soil. This is because certain fungi (mycorrhizal fungi – see page 42) are critical in storing carbon in soils, and soil culti...

Table of contents

• Cover
• Title Page
• Copyright
• Contents
• Dedication
• Acknowledgements
• Foreword by Hugh Fearnley-Whittingstall
• Introduction
• Part 1: An introduction to perennial vegetables
• Part 2: Perennial vegetables A–Z
• Appendix: Common and Latin names
• Resources
• Picture credits
• Index