Already we are seeing an increase in the occurrence of severe weather events, such as floods, heatwaves and droughts. In the future this will have huge ramifications for gardeners everywhere and could change the landscape of the UK beyond all recognition.
The world of horticulture has always been dictated by the seasons. Although the astronomical dates and meteorological dates for the start of each season don't change (apart from by a day or two), the behaviour of plants and wildlife and weather patterns have begun to change. Many now see this as outcome of climate change.
Start dates of seasons
|Season (Northern Hemisphere) ||Astronomical ||Meteorological |
|Spring ||21 March ||1 March |
|Summer ||21 June ||1 June |
|Autumn ||23 September ||1 September |
|Winter ||21 December ||1 December |
According to research,
Gardening in the Global Greenhouse , spring has advanced by two to six days per decade and autumn has been delayed by two days per decade.
Impacts on gardens
- Water shortage is likely to be the most serious single impact of climate change on gardens. With an increase in the level of rainfall during winter, and summers likely to become drier, gardeners may need to plan to store winter rainfall and irrigate in summer.
- Gardeners will need to adapt their planting and garden management practices to ensure survival of their gardens in the changing conditions.
- Gardeners will need to think about drought-resistant bedding and perennial plants like marigolds, petunias or geraniums, especially in south-facing or free-draining areas.
- Herbicide spraying will need to take place earlier in the year to have the greatest effect.
- While a warmer climate and the opportunity to grow new plants may be welcomed by domestic gardeners, heritage gardens may face particular difficulties in preserving a traditional display of plants as climatic conditions change.
- Throughout the UK, hilltop gardens will be particularly prone to drying and to gales, while low-lying gardens will be susceptible to flooding.
- Lawns will be at risk from the red-thread (Laetisaria fuciformis) disease, which thrives on warm, wet conditions, and will need year-round maintenance.
Gardens in the future
- It will be easier to grow fruit from warmer climes. Silver maple and black cherry trees could thrive in warmer weather.
- The increased concentration of carbon dioxide in the atmosphere, integral to the process of photosynthesis, will also mean that plants can grow faster and stronger. This will help in the battle against pests and diseases, as they will be more robust.
Impacts on plants
The growth of a plant is controlled mainly by light levels, the availability of carbon dioxide, water, nutrients, and temperature - all of these elements will be affected, directly or indirectly, by climate change. According to research, in Europe as a whole climate change is predicted to wipe-out between 11 and 17% of current species.
The way plants respond to drought conditions, combined with increased temperatures, will be of most concern to gardeners.
Annual plants will often flower more rapidly in conditions of water stress and will subsequently set seed earlier. This will curtail the flowering season and they will wilt and die earlier.
In the future plants in the UK will be affected by climate change in a number of ways:
- Increased carbon dioxide levels will increase rates of plant growth and perhaps development (bud burst, flowering and leaf fall)
- Changes in temperatures are expected to bring an earlier onset of growth in spring and a longer growing season
- Mild winters may reduce the yield of fruit trees, because colder temperatures are needed to break the buds
- Increased temperatures will aid the growth of more plants from warmer parts of the world
- Higher temperatures and decreased summer rainfall will cause stress, especially in plants with extensive, shallow, fibrous root systems
- Annual moisture content of soils is likely to decrease by 10-20% across the UK by the 2080s, with substantial reductions (of 20-50%) in soil moisture possible in the summer by the 2080s
- Fungal diseases will thrive with the wet winter conditions.
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Last Updated: 11 May 2012