By Sandra Gibson
Photograph by Geoff Edwards
When I was young we always went on holiday during the first two weeks in July and when we got back my mother would be found sad in the garden. It wasn’t because she was missing Blackpool but because she had missed the glorious flowering of her annual blue geraniums. A couple would remain but the main event would be over. In recent years, that same patch of geraniums has flowered at the beginning of June. This is how climate change is revealing itself at a very personal level and I think this is important – this personal experience – because the issue is so gigantic that we are mostly in emotional denial, even if we accept the facts. For example: 80 million lives will be threatened by flooding because of sea level changes; deserts are claiming adjoining agricultural lands; water shortage will create mass migration. These facts are too big to contemplate so we look away.
But we still notice things, especially in our own backyard.
Two recently published reports from reputable sources: Gardening in a Changing Climate, by the Royal Horticultural Society, and The State of the World’s Plants, by the Royal Botanic Gardens, Kew**, describe the current and probable effects of climate change in our gardens and the adjustments needed from us in response.
The growing season of central England has increased by an average of five weeks since the late nineteenth century. Our current climate is characterised by higher average temperatures, less summer rain, longer dry spells, drier soil in spring, summer and autumn, and severe storms. Plants are flowering earlier and surviving longer into the autumn – I had nasturtiums and pelargoniums on Christmas Day last year – whilst some plants that are not drought tolerant are struggling. That stalwart feature of the British garden: the lawn, is becoming more labour-intensive because it is growing faster and for a longer period. On the other hand, prolonged dry spells will leave the grass brown and parched and less soothing to the eye. The reports stress the importance of not paving over your garden to save effort, though. Never under-estimate the importance of every plot – however small – in capturing carbon, in absorbing rain (to counteract flash-flooding), in cooling the summer atmosphere and in retaining heat in winter. When times become extreme the garden has a modifying effect, so if your lawn looks surly or too boisterous replace it with woodland-style planting or shrubberies.
But not concrete.
There are implications for birds and insects too: how rapidly can they modify their life cycle to adapt to climate change? With earlier flowering and later leaf fall, what happens to the creature who hatches too late for the peak pollen moment, or who relies on fallen leaves for protection? The reports suggest that we extend the variety of plants as much as possible to maximise the survival chances of species so closely affected by exquisitely precise ecological timing.
Our trees must also be considered. Apple trees need some winter chill to stimulate flowering and fruiting, so the harvest is compromised by mild winters. In some areas, Mediterranean crops such as grapes are being cultivated instead and it seems our wine industry is doing well. Japanese maples, alders, birches, rowans and poplars suffer from die-back in summer dry periods, and it looks as if the beech tree will only survive in areas with deep soils on north-facing slopes. Bearing these issues in mind, the reports do urge people to plant trees: they remove heat-trapping carbon dioxide from the air and take up a lot of water, thus reducing flood risk. Why not consider a plane tree because it also captures particulate pollution?
More extreme conditions put plants under stress and therefore subject to pests and diseases, which will also become more rampant because of increased heat and humidity and shorter periods of dormancy. The reports suggest a careful linking of planting choice with garden conditions: a plant strengthened by its optimum environment is more likely to fight off diseases.
What other adjustments are suggested?
Climate change that dates to the start of the Industrial Revolution cannot easily be reversed and it might be too late. Historical emissions mean that climates will continue to change, even while we try to reverse it. So what can the individual do? Well, efficient composting, for a start. A healthy soil is moisture-retentive and also replaces nutrients lost through torrential downpour; a healthy soil retains carbon. It is likely that governments will regulate our use of water in the garden, so collecting every drop of rainwater becomes a minimum requirement if we are to deal with periods of drought.
Confronted by climate change denial amongst some of our world leaders, it is easy to feel powerless and doomed, but bear in mind that everyone who has a garden is empowered to fight the adverse results of negligent planning, bad decisions, corporate greed and ignorance. If you have no garden dig up a paving stone or two; put five pots on a ledge; hang some baskets by the front door. No space? Go vertical with gravity-defying vines and clematis and rambling roses. You won’t regret it and it’s a way to give something back to our beautiful blue planet, which we have so abused.
*Also known as Rose Bay Willow Herb, the prolific wild flower called Fireweed, five feet tall with spikes of magenta flowers, cheers the hearts of those whose cityscape has become a bomb site or whose buildings have been cleared by machine. The dormant seeds spring to life after destructive events such as forest or man-made fires, hence the name, Fireweed. This occasional column will celebrate the persistence of wildlife in urban conditions.
**I’m grateful to Gardeners’ World magazine www.gardenersworld.com for drawing these reports to my attention.