Designing Resilient Gardens
It’s been a reflective few weeks here. Beginning with hearing a vision for the future of landscape architecture at the international ‘Landscape 50’ conference, hosted by The University of Sheffield. A major theme of the conference was adapting to climate change and population growth. The pressure on our green spaces will only increase in time, so it will become vital that we preserve our natural spaces, and adapt our enriching gardens.
‘We need to garden our wild and wild our gardens’ Thomas Rainer, author of Planting In A Post Wild World
Rainer, one of the ‘Landscape 50’ speakers, specialises in creating plant communities in man made settings. He talks of planting in vertical layers or ‘plant storeys’. When we observe plants in wild plant communities, we see one plant emerging from beneath the canopy of others to pierce through and flower higher up.
Plant storeys, co exist or supersede each other, covering the soil. Think of the bluebells that carpet the woods in May, which are then hidden by maybe bracken, or cow parsley, then finally the tree canopy fills out and takes over the dominant photosynthesising.
A few days later I skipped off to enjoy the coastline of Pembrokeshire, with its stunning geology & wildlife. Being me, I was mostly struck by the flora and fauna – particularly the hedge-banks that characterise the area dividing lanes from fields.
A hedge-bank is a cross between a wall and a hedge. Over time these rich habitats become covered with a fine tapestry of plants; ransoms, willow herb, navel wort, creeping dead nettle, herb robert, jack in the hedge, wood anemone, stinging nettle and sticky willy; great sounding characters and a wonderful example of plant communities in nature. It was a great opportunity for me to look and learn about the strength in diversity. Examining these plants and seeing how they worked together got me thinking about what the key considerations should be in making resilient gardens for the future.
So what exactly does the future hold? Along with a likely frost-free Britain, climate change is forecast to generate greater variables in the weather; more storms, more rainwater, and then longer hot dry spells; so resilient plants will become imperative. We will have a longer growing season and therefore can utilise plants from arid countries (in gardens where drainage isn’t an issue).
Some solutions are split between urban and rural gardens where very different considerations are needed. For example; lawns, traditional and yet a high-energy use of space, will become a nuisance to maintain. A wilder aesthetic will suit rural gardens where big spaces allow for meadows, whereas in urban situations gravel gardens may be more appropriate.
Things to consider when future proofing your garden
- We can observe and work lightly with our plots rather than battle against them. For example by limiting earth moving, we can avoid interrupting natural water drainage routes.
- Create shade and shelter to screen from heat and wind ensuring that spaces get maximum use in all weather. Using hedges and shrubs rather than fences or walls will soften wind, rather than creating further problems, as well as providing habitats for wildlife.
- Raised beds can help overcome waterlogging.
- Look into SuDS (sustainable draining systems) for driveway surfaces. Note: impermeable hardstanding of more than 5m2 requires planning permission due to increased run-off and flash flooding issues.
- Collect and harvest rainwater for use in the garden.
- Intercept rainwater with green roofs to reduce run-off . Also, rainwater gardens can be designed to deal with heavy rainfall in built-up spaces.
- Soil really matters. We usually concern ourselves with what we can see in our gardens but a deeper understanding of our soils will be invaluable. As well as protecting and nourishing our soil we can plant to benefit it too. Different root structures play important roles within plant communities; where for example a dandelion’s long tap root can access nutrients lower down in the soil, as its leaves die down they make those same nutrients available at surface level, in turn then feeding a foxglove perhaps, whose fine spider web of roots lie just millimetres under the surface.
- Hooper’s Law is a guide to allow you to calculate the age of a hedgerow, by counting the number of species in it. Hedgerows are a plant community – and they gain species with age. Similarly the diversity of plants in a garden can be the strength of it.
- Use perennial planting rather than annuals or bedding plants and keep soil covered to help preserve the soil structure. We now know for example that leaving soil exposed and turning it annually degrades the soil structure and its mycorrhizal networks.
‘There are more life forms in a handful of forest soil than there are people on the planet. A mere teaspoonful contains many miles of fungal filaments.’ Peter Wohlleben
- Plant more woody plants, like shrubs and smaller trees, to lock up carbon; more evergreens especially.
- Forest gardening – a low input way to grow your own food – mimicking a forest rather than an farmer’s field. More on this soon….
The RHS has more information on Gardening in a changing climate.