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Why Perennials

Sitting on a coach on the way home from London, I was eating a meal that included roasted chestnuts. Opposite me were a couple of people eating sandwiches. I started to think about the different foods we were eating. Nutritionally they were somewhat similar, both chestnuts and wheat being good sources of carbohydrate, though the chestnuts are rather lower in protein. I then thought about the work involved in growing, harvesting and utilizing each of these foods.

With the sweet chestnuts all you have to do (once the trees have been planted and are old enough to bear fruit) is come along in the autumn and harvest the seeds - the plants will continue to yield for possibly hundreds of years without any help from you. With the wheat, however, it is quite a different matter. Here the ground must be cultivated every year in order to prepare a seed bed; the seed must then be sown; a method found of controlling the weeds; fertilizers added in order to achieve satisfactory yields; fungicides and insecticides applied in order to control pests and diseases and then large machinery used in order to harvest the crop.

This is all so much extra work, particularly when you consider that, even with all this effort put into growing it, the yields of wheat will still be less than the yields of chestnuts could be from the same area of ground. It made me wonder why on earth people had fallen into the trap of growing annual crops.

When you go on to consider the wider effects of growing annual crops such as wheat compared with tree and other perennial crops then the issue seems to move from the farcical to the totally ridiculous. Not only have we given ourselves so much extra work for lower returns, we have also devised a method of growing our food that is extremely damaging to our environment and to all the plants and creatures that live in it (which includes us of course).

Let me try and explain this in more detail and, as an example, let me first look at a field of wheat and then compare this with a woodland.

Annual monoculture

Annual crops, grown in conventional systems, demand that the soil is cultivated. The very act of cultivating the soil serves to destroy organic matter, kills much of the soil fauna and leaves the soil at risk of erosion from wind and rain. The soil structure is damaged and, with continued cultivation, the sub-soil becomes very compacted and is unable to drain properly or allow roots to penetrate and obtain their nutrients. When it rains soil is washed away. Just go and stand in a country lane on a wet day and you will see all the muddy water flowing along the sides of the lane. This is our valuable top soil, being carried off to streams and thence to the sea.

In a field of wheat all the plants have the same nutritional requirements, their roots occupy the same levels in the soil and will only be able to obtain nutrients from this one level of the soil. Any nutrients that have been washed lower down into the soil will be lost to the plants and will eventually find their way into the water system either to be washed out to sea or to pollute our drinking water. Genetically very similar, these plants are all susceptible to the same pests and diseases and all have similar climatic requirements. If one suffers, they all suffer. The system is dependent on large inputs of fertilisers, herbicides, pesticides, fungicides etc. The soil is little more than a medium to hold the plant up, and even this it is becoming less able to do well as soil structure and depth are destroyed. The Fenlands, for example, are losing 30 mm of topsoil every year.

A field of wheat is like a desert to most of our wild animals and plants - the intensive growing regime means that very few species of plants will be able to grow in the field and thus there will be very few animals that will be able to survive in and around the field. In the edition of The Guardian newspaper dated 12/08/94 there was an article about the declining population of some of our commonest species of birds. Apparently, in the period between 1969 and 1991 tree sparrow populations declined by 85%, corn bunting by 76%, grey partridge by 73%, turtle doves by 75% and skylarks by 50%. The article went on to blame current agricultural practices that have seen hedgerows destroyed, meadows ploughed up and fields harvested before the birds had a chance to finish rearing their young. It said that the dawn chorus, that enchanting time of the morning when the air is alive to the sound of bird song, is heard no more in many parts of E. Anglia, where an eerie silence now greets the dawn.

It can be argued that yields of wheat have increased dramatically in the last 100 years, from around 1 ton per acre at the beginning of the century to 3 tons or more now. But is this sustainable? No it is not! In fact when you take into account all the energy that is expended in making the farm machinery, in fuelling it, in making the fertilisers etc. and all the other things that need to be done in order to produce the food, far more energy is actually used up in growing the food than the food itself yields in energy! This ridiculous state of affairs is only possible due to the current abundance of fossil fuels, but how long are they going to last?

Woodland systems

Let us now look at a native woodland. Who feeds this with artificial fertilisers? Who sprays fungicides? Who applies the herbicides and why isn't everything eaten up by insects? Year after year the woodland produces masses of plant growth feeding a host of mammals, birds and insects. A wide range of plants grow side by side, sometimes competing but more often occupying subtly different niches in the woodland. For example, some plants will have deep root systems and these will obtain many of their nutrients from deep down in the soil in areas beyond the reach of other plants. When their leaves die in the autumn many of these nutrients will be made available to other members of the plant community. Other plants will have shallower root systems and these will obtain their nutrients from nearer the soil surface. Similarly, there will be gradations of height in the woodland, some of the plants will be tall trees, some will be small trees or shrubs, there will be climbers making their way up the trunks of the trees, smaller perennials able to grow in the shade of the trees will be found on the woodland floor. Some of the smaller plants will come into growth early in the year, before the trees have leafed out, and will complete most of their life-cycle by early summer. Thus there are different niches for plants to occupy in the soil, above the ground and in time.

The canopy of trees creates a sheltered and more stable environment inside the woodland. Temperature fluctuations are less extreme than in an open field, there is less wind and frost and so plants are less subject to the vagaries of our weather. Because of all the different available habitats there is a wide range of creatures able to live in the woodland and the more diverse the numbers of species that live in an eco-system, the more stable it becomes. The force of the rain is broken by the trees and the rich carpet of organic matter in a woodland absorbs the rain and allows it to drain into the soil and enhance the water table instead of running off into the rivers and thence to the sea, taking valuable soil and nutrients with it.

There are various fungal and bacterial activities taking place on the root systems of the woodland plants which increase the abilities of plants to take up nutrients from the soil and also produce nutrients for all the plants to utilise. Recent research has demonstrated that the greater the diversity of plants growing in an area then the greater the total amount of growth that takes place. Thus we see that a woodland is not only self-sustaining and highly productive, it can also lead to a gradual build-up of fertility, unlike annually cultivated soil which needs constant inputs if it is to remain fertile.

The value of diversity.

There was an article in the Spring 1994 edition of 'Kew' magazine. It was talking about a group of chimpanzees that live in a small area of forest, called Gombe, in Africa. The forest is a reserve and is surrounded by cultivated land. The article continued:-

'Outside Gombe, the local people are struggling to live off perhaps 30 different types of foods, mostly introduced species of plants grown in drought conditions on easily eroded soils.... But the chimps seem to be expert botanists, knowing exactly where and when the next crop of fruit will be. There may be only six major plant foods each month but, over the year, more than 150 species are used. Some of the fruits they eat are delicious and they can certainly teach us a great deal about a balanced diet and preventative health-care. But although a lot is known about the chimps' social behaviour, our understanding of their botanical knowledge and its significance to us is in its infancy. Few of their food plants have been tested for nutrients or medicinal properties.'

Selecting the plants.

• be far more productive than a field of annuals
• produce a much wider range of foods
• require far less work
• require far less inputs such as fertilizers and pesticides
• provide valuable habitats for wildlife
• be very pleasing aesthetically.

The main difficulty is that people have been selectively breeding the traditional annual crops over a period of thousands of years. In that time the cultivated plants have often changed dramatically from the original wild species (cauliflowers, brussel sprouts and cabbage all derive from the same wild plant) whilst the taste and yield has also undergone great changes. Thus the cultivated lettuce was derived from a bitter tasting poisonous plant and the wild ancestor of carrots has a thin woody root that really does not make very pleasant eating.

This selective breeding, however, has also had a number of disadvantages. We might have ended up with a lettuce that has mild flavoured leaves that go well in a salad, but we also have a plant that is very susceptible to pests and diseases, whilst it also requires a lot of attention when growing since it is unable to compete with most other plants. Thus if anyone wants to eat lettuce all the year round they have to sow seed on at least 10 occasions over the year - which means preparing the soil, weeding, watering if the weather is dry, trying to prevent the plants running to seed if the weather is hot and trying to prevent them rotting if the weather is wet. We also have to supply nutrients and organic matter to the soil if we are to produce a good quality plant. Even with all this attention, we will produce a plant that is considerably lower in nutrients than the wild plant it was bred from.

Most of the perennial plants that we recommend for woodland plantings have never been selectively bred for yields, flavour etc. Thus the harvest might be lower than you would expect from cultivated annuals, or it might be more fiddly - but all the plants on the lists below produce very tasty crops. Once established these plants will continue to yield their harvests for many years with very little work on behalf of the grower. Not only that, but they will tend to suffer far less from pests and diseases, will not require much in the way of fertilising and will be far more resilient to the vagaries of the weather. Since many different species will be able to occupy the same area of land, overall yields can be much higher than from annual plants. There is also a lot of scope for careful selective breeding in order to produce more productive and easier to harvest cultivars. Any selective breeding, however, should always take into account any potential negative effects on the plants.

A woodland garden.

1. It is possible to grow trees almost anywhere in Britain (97% of the land used to be covered with trees before people started chopping them down). What is important is to choose the correct trees for the site - if planting right by the coast, for example, then you need to select species that can tolerate the strong salt laden winds. Once the trees are established they will provide shelter from the elements so that other less tolerant plants can be grown amongst them.
2. You do not need large areas of land on which to grow your woodland. By choosing small trees it is possible to have a mini-woodland even in a small back yard.
3. Be clear in your mind what crops you want to grow and then choose the appropriate species.
4. Plant the sun worshippers on the sunny side of the woodland - most fruit-bearing species crop better when grown in full sun.
5. Taller trees should be towards the north side so that they do not shade out the smaller species
6. Be aware of the vigour of each plant and plan accordingly. If, for example, you plant a very strong-growing climbing plant into a small tree then it is very likely that the tree will be smothered by the climber and die.

There is no space in this leaflet to talk about the plants that can be grown in this woodland system - if you would like more information on these then please ask for our leaflet titled Woodland Garden Plants. However, I would like to list just a few of the plants that you could be growing to supply food all the year round.

Seeds

Araucaria araucana (Monkey puzzle); Caragana arborescens (Siberian pea tree); Castanea sativa (Sweet chestnut); Cephalotaxus drupacea harringtonii; Corylus species (Cobnuts and Filberts); Juglans regia (Walnut) and Quercus ilex (Holm oak) all bear well at least in parts of Britain.

Fruits

There is such a wide range here that I can only mention just a very few of them. Actinidia deliciosa (Kiwi fruit); Amelanchier alnifolia (Juneberry); Cornus species; Crataegus species; Elaeagnus x ebbingei; Malus sylvestris domestica (Apple); Prunus domestica (Plum); Pyrus communis (Pear); Ribes species (Gooseberries and currants) and Rubus species (Raspberries and blackberries) will provide a succession of fruit all year round.

Leaves

Allium ursinum (Wild garlic); Campanula persicifolia (Harebell); Cryptotaenia japonica (Japanese parsley); Fagopyrum dibotrys (Perennial buckwheat); Montia sibirica (Miner's lettuce); Myrrhis odorata (Sweet Cicely); Rumex acetosa (Sorrel); Tilia species (Lime trees); Urtica dioica (Stinging nettles) and Viola odorata (Sweet violet) are just a few of the species to choose from and between them you should be able to pick fresh leaves all the year round.

Roots

Erythronium species (Dog's tooth violets); Lathyrus tuberosus; Lilium lancifolium (Tiger lily); Medeola virginica (Cucumber root) and Streptopus amplexifolius are some of the more interesting root crops that you could grow.

A woodland is not the only place in which to grow perennial crops of course, there are many other habitats in which they can also be grown. For more information on this see some of our other leaflets such as The Edible Lawn, Edible Pond and Bog Garden Plants and Edible Ornamental Plants.

Database

The database has more details on these plants: Actinidia deliciosa, Allium ursinum, Araucaria araucana, Caragana arborescens, Castanea sativa, Cryptotaenia japonica, Elaeagnus x ebbingei, Fagopyrum dibotrys, Juglans regia, Lathyrus tuberosus, Lilium lancifolium, Malus sylvestris, Malus sylvestris domestica, Medeola virginica, Myrrhis odorata, Prunus domestica, Pyrus communis, Quercus ilex, Rumex acetosa, Streptopus amplexifolius, Viola odorata.

Readers Comments

Cryptotaenia japonica

Chris Brown Fri, 14 May 1999 13:44:48

I recently obtained a Cryptotaenia japonica plant from a local plant sale (Eugene, Oregon); the grower said it was an edible, so that made it a very appealing addition to my garden. As it was not in any of my horticultural reference books, I decided to do an internet search to see what kind of conditons it would flourish in. To my surprise, the North Carolina State University declared it a poisonous plant!

I then discovered your page, which confirmed my original information, which lists it as an edible plant. I don't know which source is correct, yours or the University's, but I don't think I will be eating it anytime soon!

Why Perennials

Fri Jan 19 18:47:02 2001

I am doing a science fair project at my school.My experiant is on if talking to your plants helps them grow any better. I am using perennial plants is this a good coice?

Cryptotaenia japonica

Shani Sun Aug 26 21:55:18 2001

This is what the site has to say regarding edibility of this plant.

North Carolina State University website (link - http://www.ces.ncsu.edu/depts/hort/consumer/poison/Cryptja.htm )

Poisonous Part Leaves. Symptoms Severe skin irritation following repeated contact. Edibility EDIBLE PARTS: Cooked, starchy Oriental vegetable (root) or salad greens. Toxic Principle Unidentified. Severity TOXIC ONLY IF LARGE QUANTITIES EATEN.

Why Perennials

Jesse Chisholm Tue Jul 8 02:25:34 2003

For a good answer to "why" so many annuals were "chosen" over history for agriculture, read the book "Guns, Germs and Steel" by Jared Diamond. This book has a section that talks about the domestication of plants and animals and why some were chosen and others weren't.

There is a review at this site: http://dannyreviews.com/h/Guns_Germs_Steel.html

But perhaps the simplest reason for annuals is the number of years that some perennials (for example fruit and nut trees) need to get established before they produce. The annuals produce the very year you plant them. If you need to migrate, you can plant in the new location and have a crop that year.

All depends on whether you prefer being a hunter-gatherer or a food-cultivator.

-Jesse Chisholm

Why Perennials

Vicki Morrone Thu Aug 21 16:20:46 2003

Regarding root depth of annual versus perennial. I don't beleive it is correct to say that roots of annuals explore all the same depth. I know of research that looks at differences in varieities of common bean roots that are able to explore different levels in the soil. The purpose of this research is for growing crops where the soil nutrients are limited and maximum root exploration is desirable. Have you ever dug a root profile for a tomato plant? You could go as deep as 11 feet! so the diagram needs qualifying and yes tomato is really a perennial but in North American we grow it as an annual due to our temperate climate.

Excellent Article!!

Aaron James Schnebly Sun Nov 9 06:31:37 2003

I agree with much of this article, although I think annual crops and modern growing techniques are a blessing to a large extent. But, annual crops would be much better if they were broken up by swaths of woodland crops (i.e. fruit trees, nut trees, and berries) so that there wouldn?t be endless fields of a single crop. Crop rotation and companion planting should be much more common with field crops. This article illustrates these points beautifully, and brings up many other valid points. I have planned to create woodland garden to surround my home for a long time now. A woodland garden in Arizona would be different from an English woodland garden (irrigated for one), but this article nonetheless confirmed my ideas and gave me more material to work with. I think this system would be most valuable around homes and towns, where people were nearby to micro-harvest. Most of the desired annuals could be grown in gardens and small fields with minimal impact on the environment. I imagine that these woodlands would have a very pleasant and park-like atmosphere, granting relief from the city and/or endless fields of single crops. This would bring nature closer to the people and the people closer to nature. I see this as one step closer to recovering the Garden of Eden.

Why Perennials

Sun Nov 9 06:49:54 2003

I agree with much of this article, although I think annual crops and modern growing techniques are a blessing to a large extent. But, annual crops would be much better if they were broken up by swaths of woodland crops (i.e. fruit trees, nut trees, and berries) so that there wouldnÂ’t be endless fields of a single crop. Crop rotation and companion planting should be much more common with field crops. This article illustrates these points beautifully, and brings up many other valid points. I have planned to create woodland garden to surround my home for a long time now. A woodland garden in Arizona would be different from an English woodland garden (irrigated for one), but this article nonetheless confirmed my ideas and gave me more material to work with. I think this system would be most valuable around homes and towns, where people were nearby to micro-harvest. Most of the desired annuals could be grown in gardens and small fields with minimal impact on the environment. I imagine that these woodlands would have a very pleasant and park-like atmosphere, granting relief from the city and/or endless fields of single crops. This would bring nature closer to the people and the people closer to nature. I see this as one step closer to recovering the Garden of Eden.

Why Perennials

rafix Mon Nov 17 13:47:12 2003

1. any plant is eatable (the dosage is extremly relevant!) so for instance a amanita muscaria or other so called toxic plants can harm or kill you only if you eat them un prepared (uncooked-unwatered,like bitternes can be wash out with several houers treatments )or just a overdose 2.apropos perennial cultivation thats very convinient endeed,but the anual crops should be cultivated complimantory. lets reencounter us urgently with the laws of nature. see my page below: we are all one!

Link: futura idea

Why Perennials

Jonathan Thu Jun 23 2005

Out in the US northwest they are now breeding (not engineering) perrenial wheat. They started by taking domesticated wheat and cross breeding with wild perrenial grasses. They now have plants which have continuosly produced for 5 seasons. These strains are bred for the dry climate of eastern Washington State, so I'm curious what the result would be in wetter climes.

Why Perennials

jjjjjjjjjjjjjjjjjjjjjjjjjjjj Wed Nov 9 2005

It doesn't say a thing about the disadvantages of artificial fertilisers this site is truly dreadful and disgraceful this site is a complete waste of time and it's also a scam

Why Perennials

Krystle C. Thu Dec 15 2005

Fantastic article. It reminds me of one day at work (on a farm), when a Jamaican co-worker was going around collecting wild "callaloo" which was growing like a weed all over the place, and makes for a common Jamaican dish; meanwhile, there was a half acre planted with corn that required a ridiculous amount of maintenance. What a difference.

SustainableWays.com

Why Perennials

lkz5ia Fri Dec 16 2005

Indeed, perennials add a lot to the food system. I feel annuals do add value to the system, too; as long as they aren't planted in big monocultures. I've started eating Linden leaves this year, which tastes mild like lettuce. Pfaf.org goes into good detail of many of varieties of plants that have use for a simpler and more fulfilling life. As the article states, perennial system takes less energy and is environmentally safe. And, if trees such as apples are integrated into the woodland system they tend to not suffer from as many pests as when planted in monoculture orchards. The natural system has a way of correcting itself when a population explosion of pests is counteracted with a a balance of predators. I've also added bamboo to the perennial equation With the many uses of bamboo, it should be grown where climates allow it to survive and prosper.

Where bamboo-minded people share knowledge and pics.

Why Perennials

Sat Apr 8 2006

Very helpful, thank you. Keep up the good hard work. 0 0 * V

Why Perennials

Sat Apr 8 2006

jjjjjjjjj you are a pathetic hypocrite who has no life to insult this site. If it's so bad then try making a better one. A large amount of effort has gone into this site and your pathetic babbling does not help. SCAM??? Are you that stupid and uneducated. Please go back to school. This site is good, jjjjjj is and idiot :-)

Why Perennials

ecoradical Tue Jul 18 2006

Ok, so we need to all go out and live in and manipulate natural ecosystems to acommodate our "environmentally friendly" woodland garden. First of all that would require a person to be financially able to purchase the land. Not applicable to most! Second, to make it convenient you would have to live nearby, thus build a house nearby (good ole urban expansion). Houses are not very environmentally friendly. Third, if you dont build a house there you have to drive to it. Driving uses fossil fuels. If everyone was driving to thier own little "gardens of Eden" more fuel would be used than a piece of farm equipment. In fairness, i guess you could ride a bike. Who has the time to ride a bike to thier little slice of heaven outside of town? So, in order to feed people that cant afford to own land, drive a lot, or dont have the free time to bike to thier garden and grow food because they work for a living; we grow large monocultures that are easily harvested and economically feasible. The underlying problem with creating a perfect system is that it has to economically feasible. This article does not look at annual and perrenial systems fairly as pointed out above. People that can call others a hypocrite be reading two sentences must be well educated (sarcasm). Sorry if this was not well written, please dont call me stupid and uneducated because i didnt want to waste time with this site. I just stumbled across this sites stupidty and had to write something to add to the stupidty.

Why Perennials

Cathy Wed Oct 4 2006

I agree, this site has many facts and information that I enjoy. and MR. jjj was overly irrate I find, when there is clearly so much info that is available and well presented. I've bookmarked this site, will keep enjoying it. This after all is not the Bible and if there is info that is not mentioned, then perhaps using this page to ask for it would have been more useful than being RUDE!!

Why Perennials

Curt Sat Jul 14 2007

Thanks for sharing this information it is very helpful. I can see a whole industry being developed to promote edible perennials.

Why Perennials

Hal Fox Mon Jan 7 2008

Dear Friend, In my garden in the bench area east of Salt Lake City, Utah, I began by digging out large and small rocks that were in the almost barren ground. Then I began composting all of he scraps from my kitchen and digging those scraps into my garden spot where the rocks had been moved. In this fashion, over the years I now have a couple of feet of soil that I have developed. In this soil I now produced most of the food that we eat. In addition, I have planted three peach trees. From these trees we bottle over one hundred quarts of peaches for our winter use. The message is that some farmers lose the soil. Some farmer reserve or build up the soil and provide the food that we enjoy. Best regards, Hal Fox, a former farmer when a youth.

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