Principles of Designing Gardens for Wildlife
By Richard Burkmar
All this talk of wildlife gardening is a double-edged sword. On the one hand it's a useful label because it's
- very descriptive,
- easy to remember,
- able to fire the imagination (particularly of the young).
On the other hand it's misleading because it
- implies that it should be considered separately from other facets of horticultural technique,
- implies an unhelpful distinction between wildlife and 'other' gardens,
- risks alienating people well versed in established facets of horticultural technique.
And if you thought that there is a clear-cut distinction between wildlife and 'other' gardens or that we really should consider wildlife gardening techniques in splendid isolation, then think againif you thought that there is a clear-cut distinction between wildlife and 'other' gardens or that we really should consider wildlife gardening techniques in splendid isolation, then think again: a wildlife-free garden does not exist, and there isn't a 'wildlife garden' in existence which hasn't, or wouldn't, benefit from the application of standard horticultural techniques established over centuries.
Nevertheless, we are talking about a relatively new and rapidly developing facet of horticultural technique, and to do that sensibly, we have to give it a name: wildlife gardening seems to be the de facto. A popular alternative favoured by some, biodiversity, seems to me to be too woolly, and at least equally misleading, when applied in this context. Oh - and if you want to get children interested, go for wildlife gardening over biodiversity every time!
We should consider 'wildlife gardening' as a term similar to 'organic gardening'. Organic gardening also describes a set of principles and horticultural techniques that can be applied to any garden; and this, I believe, is how we should think of wildlife gardening.
The four cornerstones
Just as there are some fundamental principles of organic gardening (e.g. avoiding chemicals), there are some principles that it pays the wildlife gardener to keep in mind. To make your garden as attractive as possible to animals you must make provision for
- breeding places.
Native plants are often used to help us make these provisions (more of that later) and of course they can be considered 'wildlife' themselves, but if we were only concerned with growing native plants, established horticultural techniques would generally serve us very well on their own. Animals, however, can quickly vote with their feet (or wings) and if your garden does not give them what they need, they will look for somewhere else that doesAnimals, however, can quickly vote with their feet (or wings) and if your garden does not give them what they need, they will look for somewhere else that does.
The nature of these four cornerstones; food, water, shelter and breeding places, can exhibit enormous variation depending on the target animal group. Breeding places for birds, frogs, butterflies and leaf-miners may all be very different. Conversely, a single habitat feature can provide different cornerstones for different animals: a garden pond, for instance, provides an important drinking and bathing facility for birds as well as a breeding place for frogs and other animals.
The four cornerstones are useful when we consider the requirements of a species, or a group of related species and by doing so we can get an overall picture of the kinds of micro-habitats we need to build into the fabric of the garden. But if we are thinking in terms of general garden design, as we are here, we must consider some more general principles, or attitudes, that we can adopt in order to make gardens more amenable to wildlife in general.
It's been said many times before, but it bears repeating; relaxing your attitude towards nature is the single greatest thing you can do to make your garden more attractive to wildlife. Look upon nature as a partner, not an adversaryLook upon nature as a partner, not an adversary. This does not mean that to be a wildlife gardener you must adopt a naturalistic garden design; the way your relaxed attitude manifests itself must fit in with the overall design of your garden.
You can still be a wildlife gardener within the idiom of a formal garden There's no doubt that it is easier to adopt wildlife gardening techniques in a naturalistic garden, but I think that wildlife gardening has suffered from confusion with the idea of naturalistic garden designs. People sometimes think that you must work with a naturalistic design in order to be a 'wildlife gardener', but that's no more true than the idea that you have to have a vegetable garden to be an 'organic gardener'.
You can still be a wildlife gardener within the idiom of a formal garden, perhaps one where native plants aren't used at all; it just requires bucket loads of imagination, ingenuity and a relaxed attitude towards working with nature.
Water features wildlife
My own semi-formal pond three months after its creation. If relaxing is the single greatest thing you can do in your head, then probably the single greatest thing you can do 'on the ground', is to provide some sort of permanent water body, or pond, for wildlife. If you fill a bucket with water and leave it unmolested in the garden during the summer, its incredible how much life colonises it after just a few days. Creating a pond is probably the best way to bring people and nature together in the garden.
Your pond could be a full-blown 'wildlife pond', a formal rill or a just tub sunk into the ground: the variations are endless.
The precise nature of the pond you create depends on the overall design of your gardenThe precise nature of the pond you create depends on the overall design of your garden. The term 'wildlife pond' is very often used to describe a certain naturalistic pond design which, because of its soft edges, natural setting and gently shelving sides, tends to take up a lot of room. We can't all afford this kind of space and, very often, a pond of this kind will not fit in with the overall garden design. Thankfully wildlife is not too fussy about the kind of water it colonises and whilst the 'wildlife pond' may represent an ideal, we can satisfy many of the requirements of wildlife with ponds of other designs.
Nooks and crannies
Nature loves heterogeneity, or patchiness and, fortunately, so do most gardeners. The greater a garden's variety in terms of planting, structure, seasonal interest, hard-landscaping materials or just about anything, the more attractive it's likely to be to wildlife. Most gardens, of all kinds, have sufficient flora to attract a large number of wild animals (principally insects and other invertebrates) into the garden. The plants often provide these animals with food: one of the main cornerstones we talked about earlier. By providing some of the other cornerstones, we can do a lot to make the gardens even more valuable to these species; perhaps even to the extent where many of them can satisfy the requirements of their whole life-cycles within the garden.
This 'habitat basket' is essentially a wire basket full of broken bricks and small logs - I submerged a couple of these in my pond to diversify the habitat for invertebrates. One of the simplest, yet most effective, ways we can provide some of these other cornerstones is by making our gardens structurally more heterogeneous. When we think about the scale on which many of these animals operate (i.e. very small), the structural enhancements we make do not have to be great - or even very noticeable: think on the scale of nooks and crannies. By providing more nooks and crannies ('microhabitats' if you like) around the garden, we can do a lot to provide shelter and breeding places for a whole host of invertebrates which, in turn, can provide food for other animals like birds and mammals.
The ways in which you can provide these nooks and crannies is limited only by your imagination. If you are building a natural stone wall, you could consider doing it dry-stone (i.e. without mortar): the gaps between the stones will provide microhabitats for hundreds of species. incorporating such invertebrate microhabitats into the design of gardens of all kinds is one of the most basic and effective techniques that all garden designers could employ to enhance the biodiversity, or wildlife value, of their gardens If you prefer to use mortar or are building a more formal wall altogether, you could still design-in some 'formal' nooks and crannies! As I said, your imagination is the limiting factor. Log piles and loose stones are valuable habitats and most naturalistic gardens can accommodate them easily. In more formal gardens, we need to be more resourceful: considering hiding such features away (e.g. under decking or under a shed) - the animals will still be able to find and use them. I believe that incorporating such invertebrate microhabitats into the design of gardens of all kinds is one of the most basic and effective techniques that all garden designers could employ to enhance the biodiversity, or wildlife value, of their gardens. In the future we will probably consider these wildlife gardening techniques as standard practice in the design of most gardens.
The use of native plants in the garden is probably the most misunderstood and contentious of all the techniques of wildlife gardening. Some people consider the two things synonymously, i.e. that wildlife gardening is gardening with native plants; I hope I've already said enough to dispel that idea. However, neither is there any doubt that native plants occupy an important position in the armoury of wildlife gardening techniques and if you can accommodate some native plants into your garden, you will find that attracting wildlife is easier.
Native plants, particularly woody perennials like trees and shrubs, tend to have more invertebrates associated with them than their non-native counterparts (Southwood 1961). This is because these native plants have co-evolved with our native fauna over thousands or years and they've developed intricate symbiotic dependencies: plant and animal often depending on each other in some way to fulfil the requirements of their respective life-cycles. Some recent research (RHS Biodiversity Conference 2002) has suggested that the link between native plants and garden wildlife (particularly non-woody natives) has been overstated, but the jury is still out on that one.
Clearly its easier to incorporate native plants into a naturalistic garden design, but it should not be impossible to use some native species in almost any garden. There's no reason why native plants cannot feature in a formal design: in all important biological respects, they're no different from the cultivated plants which we do use in such situations. The big differences are in our heads. If we can get over the negative feelings that many native plants engender in us when we find them in the garden (often for no better reason than that's the way it's always been), we will open up a new world of possibilities. There's great fun to be had with the idea of putting native plants in formal situationsThere's great fun to be had with the idea of putting native plants in formal situations - there are endless possibilities for the juxtaposition of these two 'worlds'.
Most people have an awkward corner where nothing seems to want to grow, but nature can find out what grows there if you let it. If you use your partner, nature, to see what colonises under its own steam, you may find something which is actually rather attractive and would work in your garden - or it might suggest to you one of its cultivated cousins.
The biodiversity found in the average garden rivals some of the richest natural habitats in the world. The amazing diversity of insects, in particular, that we find in gardens owes a great deal to the plentiful supply of nectar and pollen. Perhaps many of the insects that visit gardens in search of these high energy food sources have to go elsewhere to fulfil other aspects of their life cycles, but that doesn't diminish the usefulness of our nectar and pollen-packed borders.
By accentuating the availability of these highly attractive food sources we can make our borders even more valuable to visiting insects. There are several useful points to bear in mind if you are trying to get the most out of your borders from the insect's point of view. These crocus are a valuable food source for many insects emerging from hibernation.
- Use a range of species to maximise the flowering period and therefore the time over which food is available to the insects. We naturally try to do this anyway because we like to see blooms for as much of the year as possible.
- Include early bloomers. Early spring is a critical time for many insects - particularly those which hibernate over the winter months. A good high-energy feed for these insects as they come out of hibernation can be the difference between breeding success and failure.
- Don't worry about the provenance of the plants; our natives are commonly outstripped by many garden flowers in terms of the quantity of nectar and pollen they provide. Most insects aren't fussy where they source this particular delicacy!
- Go for simple flowers where the nectar and pollen remains accessible to the insects. Many highly developed cultivars, e.g. those with double flowers, are sterile or are not easy for the insects to tackle.
- Include plenty of species where the nectar and pollen is available near the surface of the flower rather than tucked away in a long flower tube. This will make it accessible to more species.
Chris Baines (How To Make a Wildlife Garden) used the analogy of a service station to describe how we can attract the passing trade of animals into the garden. We've already looked at how we can do that for insects by providing them with nectar and pollen-packed borders. There are a number of other techniques that can be used for other groups of animals. Most involve feeding (or watering) since hunger and thirst are two of the most pressing motivators for animals and those for which animals will most readily adapt their behaviour.
Most gardeners underestimate the importance of water and its power to attract animals into the gardenMost gardeners underestimate the importance of water and its power to attract animals into the garden. After creating a new garden pond, one of the most satisfying milestones in its development for me was the sight of birds drinking and bathing there. But you don't need a pond in order to provide an attractive watering hole for birds and other animals; almost any body of water you provide in the garden will be used by them. Ideally, whatever you provide should be deep enough so that it doesn't quickly evaporate in sunny weather or completely freeze in the cold. Gently shelving edges are ideal so that the birds can choose the depth which best suits them when bathing. I recently spent a few days with my parent's during some warm and dry weather; their garden is in an area of the country where there are few streams and other bodies of fresh water. The bird bath in their garden, which is the ornamental sort you can buy from most garden centres, was a hive of activity all day long - it rivalled a bird table on a winter's day.
Blue tit taking sun-flower seeds from a feeder.
Feeding birds in the garden is moving from an art form to a science. A great deal of research is being done into the suitability of various foods and the best ways of providing delivering them to the birds. Over recent years suppliers have taken the tools at our disposal, both in terms of food and feeders, to new levels. It is now widely accepted that, contrary to advice given a few years ago, it is better to continue feeding birds through the summer as well as the winter. One reason for this is that young birds suffer very high mortality after leaving the nest and providing extra food for them may ameliorate this. We should make sure however, that food we supply during the breeding season can be easily digested by birds. So if, for example, you continue to feed with peanuts through the spring and summer, you should ensure that they are provided using the sort of feeder that requires birds to break them up in order to extract them. This prevents whole peanuts (which can choke a young bird) being fed to nestlings. Supplementary feeding, both for birds and other animals, is one of the simplest things you can do in any garden to bring instant results (for example see Through the Garden hedge).
Cotoneaster laden with berries during the winter months We can also provide food for birds and other animals by planting a range of berry-bearing shrubs in the garden. A number of native species, such as hawthorn (Crataegus monogyna) are very useful in this respect but several non-natives like the cotoneasters are also very attractive to berry eating animals. A range of shrub species provides a larder of fruit which will appeal to a wider range of animals.
From an ecological point of view, using chemicals in the garden is not a great idea and if you are wildlife gardener you should avoid using them if at all possible. Chemical weaponry is a very blunt instrument: you can never be sure that the species of animals or plants you want to target are the only species affected. However, you may be surprised to learn that by adopting wildlife gardening techniques to attract more species of wildlife, you actually lessen the risk of being the victim of pest species.
In nature, the population levels of plants and animals rarely reach pest proportions because the intricate interdependencies between thousands of species living together creates a more or less stable ecosystem. We see the most notable outbreaks of pests in environments where we have deliberately reduced biodiversity; e.g. arable farmland where many species of plants and animals are deliberately eradicated in order to maximise crop production. The reduction in biodiversity makes the ecosystem less stable and consequently more vulnerable to massive population changes in some species.
By promoting biodiversity, wildlife gardening techniques actually give us much more stable garden ecosystems where pests are more naturally held in checkBy promoting biodiversity, wildlife gardening techniques actually give us much more stable garden ecosystems where pests are more naturally held in check; thus reducing the need for chemical pest control methods. Birds, bats, frogs, toads, hedgehogs, hoverflies, ladybirds, lacewings, ground beetles, even wasps: these are just a few of the natural predators of 'pest' species in the garden. We may not distinguish, to any great extent, between pest and non-pest species when we garden for wildlife, but by encouraging as great a diversity as possible, we always ensure that the pests have plenty of adversaries to keep them in check.
Chris Baines, in his book How To Make a Wildlife Garden, describes how visitors are always surprised to see how much fruit and veg he grows in his naturalistic garden where insects are encouraged to the full. But the truth, as he points out, is that it's easier to garden organically in a garden which is wildlife friendly. In fact, organic and wildlife gardening should be regarded as complementary horticultural practices.
First published April 2003. Last revised December 2003.
Copyright Richard Burkmar 2003. Permission is hereby granted for anyone to use this article for non-commercial purposes which are of benefit to the natural environment as long the original author is credited. School pupils, students, teachers and educators are invited to use the article freely. Use for commercial purposes is prohibited unless permission is obtained from the copyright holder.