Gardening in a changing climate
Facing the facts
Making a difference in the garden
Richard Bisgrove offers some personal advice on what gardeners can do to minimise their carbon footprint in an effort to garden more sustainably.
Be adventurous with new plants and ideas. My olive and bananas are doing well and my Albizia was flowering better each year until a summer gale felled it; the new suckers look promising, however. I failed with Strelitzia (bird of paradise) last winter but will try again.
Provide more shade for summer, using pergolas and similar structures, so that you can continue to enjoy the garden when it is too hot to work in it. If plants succumb to recurrent droughts or new pests, simply try growing something else.
The ‘grasses and perennials in gravel look’ is both drought tolerant and low maintenance, but is not the only option for UK gardens in a warmer future (planting styles).
Be flexible and adaptable. Much of the armoury of the gardener rests in the ability to avoid problems rather than trying to control them. Keeping the garden in a vigorous condition, with a diverse range of youthful plants, will help guard against disaster as, if one plant fails, the gap can easily be filled.
The 1987 great storm (left) was so devastating because there had not been a similar storm for nearly three centuries. Trees had grown to great sizes, and were ultra-susceptible to the winds when they came. The initial result seemed disastrous, but the long-term effect was a regeneration of many moribund gardens and a healthier, more resilient tree population.
Be grateful that we live in what is still a green and pleasant land. Most of the effects of climate change in UK gardens in the 21st century should be manageable, and we have an excellent infrastructure, from fire brigades to insurance policies, to support us in what are predicted to be more extreme events, such as floods and storms. In recent years, for example, a number of damaging tornadoes (right) have hit the UK. Insurance premiums will increase no doubt; rising sea levels may affect low-lying areas of East Anglia and the South East. Yet such problems are relative: much of the developing world faces not brown lawns or wilting wallflowers but droughts, desertification and inundation by rising sea levels that threaten livelihoods and lives.
Be greener: store rain water for use in dry weather, and store carbon inside plants and in the soil. Temperate forests store about 8kg of carbon per sq m (15lb per sq yd) above ground and 25kg (56lb) in the soil. Grassland stores less than a kilogram (2lb) above ground but 24kg (53lb) in its root mass and soil. Arable land stores little carbon above ground and only 6kg (13lb) in the soil.
Organic and permeable materials (left) are better for paving than concrete, which causes large amounts of carbon to be emitted into the atmosphere in its manufacture and transport, and offers nothing in return. Deep cultivation of the soil to add organic matter, organic mulching, and growing woody plants all help to remove carbon dioxide from the atmosphere (and also help the soil absorb and store water).
Think ‘sustainable’ when buying gardening tools and working in the garden. Sharpen the shears, abandon the powered hedge-trimmer, and invest in a hand-propelled mower. It is still possible to find push mowers and they are fine for small gardens. For larger lawns, a cylinder mower uses much less fuel than a rotary. The savings in carbon emissions to be made by such changes are small, but they add up if everyone contributes, and the spread of energy consciousness from individual gardens to the rest of the globe may just tip the balance.
Richard Bisgrove is Senior Lecturer in Landscape Management at the University of Reading