IMPACT ON GARDENS FROM GLOBAL WARMING
Childhood memories of sunny summers getting burnt on Broughty Ferry beach followed by hard winters when we could ice skate on the roads, (very few cars around) and have plenty of snow for sledging, snowmen and igloos, all belong to my generation. I was not able to offer my young family the same fun as they grew up with a lot less snow visible and although the summers seemed fine there was a lot more wet days if your holiday was at home.
However there was always the extreme conditions of a very cold winter, six foot snow drifts, local floods you will not forget, and every ten to fifteen years a very hot summer.
My gardening career started during the 1959 summer heatwave as an apprentice gardener in Dundee Parks Dept. working in the Howff cemetery. A glorious three months ended when the rains came in September and flooded the Howff and many other places.
Gardening activities force you to work with the weather so you become aware of weather patterns and how they change over your lifetime.
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| Date Palm |
I was working in Darlington Parks Dept during the 1976 heatwave. Our main bedding displays relied on geraniums and petunias which could not have been better. We won the Regional Britain in Bloom Award. However the heatwave had other effects, especially on the greenfly pests. Farmers in east Anglia were applying high levels of nitrogen fertiliser to increase grain yields. This also gave a lot more leaf content which combined with the hot summer caused breeding greenfly to reach plague proportions. Once they had devastated East Anglia they took to the air to find new pastures. A drift extended from Kent to Newcastle and scientists estimated the weight to be in excess of 200,000 tons of greenfly.
That summer I was on Scarborough beach when the sky darkened from the sea and expecting a thunderstorm got quite a shock when the plague of greenfly arrived.
Hitchcock could not have done it better!! The sea and sand turned green and everyone ran for cover. The following year there was a mini plague of ladybirds which had been feasting on the greenfly.
Gardens, farm crops and the outdoor natural landscape will all be affected as global warming changes our climate. Future generations will need to adapt to climate change as this generation embraces the changes, assesses the impact and takes steps to alleviate the problems.
Changing weather patterns
The UK has always had a different local climate for different areas, being affected by proximity to the sea, and the gulf stream, hills and mountains, built up urban areas, winds and geography. The south is generally warmer than the north, the west wetter than the east, but extreme weather conditions can affect any area with tornadoes in the Midlands, hurricanes in the south and flooding just about anywhere. Counting 2010 we have had four very wet years following the record breaking heatwave of 2006. June was truly flaming, but then the rains came in July and hopefully when you read this it will have stopped. However the south of the country has been basking in a glorious heatwave with gardens desperate for water. My garden hose has not been used for four years.
Mild winters have seen the snowdrops flower a month earlier than normal followed by other spring bulbs all early. Grass cutting always started first week in April, but now it is more likely to be mid March and the season finishes, not when the grass stops growing but when it is too wet to put the mower over the ground.
The Good
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| Fig Brown Turkey |
Gardeners love to try out new plants and now with a warmer climate the time is right to experiment with those exotics we admire from holidays abroad.
There is a whole range of palm trees worthy of planting from the cabbage palm, Cordyline australis to the date palm, Phoenix canariensis and those colourful Bougainvillea's might one day become common in UK.
It may be normal to grow our tomatoes outdoors rather than under glass and sweet corn could become a major crop.
Already I am having success with peaches and figs and some types of outdoor grape vines and as warming continues it is quite possible that Scotland could have numerous vineyards especially as it may become too hot for their success in France.
Pete Gottgens is prepared to be a leader in this field by establishing a vineyard on the banks of Loch Tay with his experience of growing grapes in South Africa. He hopes for success by choosing an early variety, Solaris suited for a northern location. We may no longer have very cold winters, (last winter being an extreme one off), and our summers may be getting warmer, but that is tempered with the prospect of a wetter summer and less sunshine hours. Scotland's first vineyard will be a barometer for the future. Gardeners will be encouraged to experiment with a range of grape varieties grown in more favourable locations with less incidence of rainfall and more sunshine hours.
In time, cherries, nectarines, apricots, citrus fruits and dare I say bananas and olives could well be grown on our Carse of Gowrie.
The woodland landscape could see more sweet chestnuts, walnuts, and eucalyptus.
The Bad
A climate that progressively gets warmer will affect many of our trees e.g. beech does not like dry soils. Herbaceous borders, rhododendrons, azaleas and lawns require moist soils so could suffer from too dry conditions. Soft fruit including raspberries, strawberries and blueberries would struggle, but saskatoons can tolerate drier conditions.
Many fruit plants require a period of winter chill to set fruit buds without which the following years crop is greatly reduced, e.g. blackcurrants.
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| Sweet Corn |
It was always good gardening practice on allotments to complete winter digging before Christmas leaving the surface rough to allow frosts to break down the soil surface, but with mild and wet winters good digging opportunities are few and far between. In spring a poor soil surface restricts the germination of seeds.
Plum trees flower so early that there is often not enough insects around to pollinate the flowers thus reducing the crop. I do not mind hand pollinating my smaller peach tree every day with a fine sable brush in March, but the plum is twenty feet tall. Forget it !!
The Ugly
The changing climate not only affects plants, but also animals, insects and diseases.
Mild wet winters and wetter summers up north give rise to the spread of damping off, blight, root rots, scab and mildew. Potato blight can be problematic so make sure the variety has some tolerance or resistance to it. Similarly roses are suffering badly from black spot, rust and mildew so only grow those varieties strong enough to withstand an attack.
However the root rot, phytophthora has many types that affect many different plants and could become a major problem in gardens as well as raspberry fields.
Two generations from now could see a massive change in the horticultural and agricultural landscape.
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