Gardens and Conservation
There is a need for a full review of the evidence for such an important subject, so this page provides only an outline of the issues.
Why gardens are often overlooked for conservation
It’s likely that most people (and unfortunately most politicians and planners) wouldn’t think of gardens when they consider important conservation areas.
It is clear that gardens are artificial habitats, which have existed globally for only some 10,000 years, and in the UK for about 6,000 years (and which have changed considerably in style and content in that time). Garden animals and plants haven’t had hundreds of thousands of years to co-adapt.
By making a garden, people tend to overcome the sort of soil problems (waterlogged, very dry, extremely chalky or acid) that are needed by highly specialised plants, and gardens are full of disturbance for shy wildlife. This is why they tend to support relatively easy-going or generalist species that (in the past at least) were common enough not to be a focus for conservation concern. Very few ecological studies were made in gardens until the last decades of the 20th century, and for a long time they were beneath the radar of most naturalists and conservationists.
Why gardens have so much nature conservation potential
Over the past few years, nature conservation has undergone a radical shift. Previously, there was an assumption that ‘common’ wildlife didn’t need any help and could look after itself; attention was therefore focused on rare species and habitats that seemed ‘on the brink’.
Recently, there has been a welcome shift, with a realisation that wildlife is struggling across our landscapes, and that much common wildlife is now in decline. The emphasis of much wildlife conservation is now on ensuring that our entire environment remains biodiverse, and that includes gardens.
While many naturalists retain a special interest in rare species, practical conservation now focuses on species considered threatened, and on the habitats that sustain them. On both counts, gardens should be back into the mainstream of conservation thinking.
This website provides evidence that good ordinary gardens are bursting with wildlife species, and are generally better for wildlife than most of the farmed countryside, to the extent that having gardens nearby improves agricultural yields by supporting pollinators. Collectively, gardens constitute a very big and valid habitat, and they looking after a lot of wildlife.
Plants are not very mobile compared with animals, and except for those that produce spores or have wind-blown or bird-carried seeds, can’t get to your garden without your help. More importantly, most of them (with some notorious exceptions) can’t easily get out again and spread more widely.
The average period of house ownership is 11 years, so the life of gardens is often short as new owners come in with new designs that often mean digging up existing gardens and replanting. This means that rare wild plants are unlikely to be conserved effectively in ordinary gardens without a substantial level of organisation.
Gardens may not be ideal places to protect rare native plants from extinction in the long term, but they can be used by keen botanists to study their ecological requirements, such as “are they self-fertile” and “do slugs love them?” Seed collected from rare or local wild plants can be propagated in gardens and the seed bulked-up and harvested for re-establishment projects.
Gardens are the best places to conserve old varieties of domesticated plants, and this could be a vital resource for future plant breeding. People who choose to plant native species are also helping themselves and others to appreciate their beauty, and build a greater concern for looking after these plants in the wild.
Unlike plants, animals can choose, at least to some extent, where to live, and if they like your garden, and it has all the resources of food and habitat needed for their life cycle, they will flourish there. If someone subsequently paves over your wildflower meadow, the animals hopefully will find somewhere else.
We really don’t know enough about how gardens swap species in and out of the surrounding countryside, but we do know that in very dry summers, all sorts of insects, including silver washed fritillaries and other rare butterflies, come into nearby gardens as the last available source of nectar. If more gardens were made as wildlife-friendly as possible, their benefit to surrounding rarer species might be enhanced.
It is also possible that planting some carefully chosen and garden-worthy native plants (in addition to the mainly non-native plants that support common wildlife species so well) could provide a way of encouraging some our less common insects, especially moths and butterflies to expand their range, and allow isolated populations to mix. This is discussed more in the native or non-native plants section of Plants and Planting.
Gardens and Priority Conservation Species
The UK conservation organisations have recognised a number of key habitats and species of particular conservation importance. Sixty five Priority Habitats are recognised, and gardens could be relevant to Ponds, Arable Margins, Hedgerows, Traditional Orchards and Open Mosaic Habitats on Previously Developed Land (such as brownfield sites). This potential needs careful exploration, and could prove a valuable approach for guiding some gardeners with particular interests.
No less than 1,150 Priority Species have been recognised. Although we generally assume that gardens won't support many specialised species, 29 animal and 16 plant species which occur in gardens (sometimes commonly) are listed as priorities for conservation. We have made a list of these garden priority species
. This list is probably minimal since it is unclear how many of the more obscure insects do actually make use of gardens. The harder you look, the more species you will find, as Jennifer Owen discovered in her ground-breaking study