My Climate Change Garden

How apt these words from Robert Heinlein were today!

Woke up to brilliant sunshine and temperatures of 20c but, as I took a train and carbon free boat ride to the Hampton Court Flower Show, the weather changed. Great big clouds moved across the sky casting a shadow over the 25 acre show ground.

By contrast, the ever impressive Hampton Court displayed the Union Jack at full mast in the only shaft of sunlight for miles. Henry V111 would have been proud to see the many visitors admiring his beloved abode as they walked along the River Thames to the Flower Show.

I headed straight for the Met Office Climate Change Dome to check out the information displays. There was an excellent one about pests that have arrived from overseas in the past ten years as a result of our warmer summers – more on that in another blog.

Popped into the Climate Change TV studio which was full of budding weather readers giving their version of a future climate change scenario which was automatically relayed to the big screen outside – see right picture below. It was great to see so many children engaging with this idea as they will be dealing with the reality of climate change in 40-60 years time. I wanted to record my own weather predictions but the queue was too long and I had to get back to the Dome for the Climate Change talk.

These ran every hour and combined the weather knowledge of the Met Office with expert advice about gardening in a changing climate from the Royal Horticultural Society – one of the organisations providing information about climate change in the garden – apart from me of course!

The talk explained what is happening with our weird weather systems and how gardeners everywhere in the UK must start to adapt to new climatic conditions now so that they are prepared for the next 50-80 years of predicted higher temperatures and heavy rainfall patterns.

It was extremely reassuring to hear the experts confirm what I have been saying about the uncertain future for our gardens on this blog and at http://www.globalgardening.org . They predict that it will be a mix of good and bad news for the UK,with too much water in the winter and too little in the summer. If the Hadley Centre climate change scenarios prove to be correct, then, by 2080, we could be cutting our lawns on Christmas Day due to milder, wetter winters and picking bananas in the South West as summer temperatures are predicted to reach 42c.

The RHS expert explained how the extension of the growing season has become particularly noticable. He described how this is defined by the number of days when the mean temperature rises above 6c. In the past 50 years this has increased by 20 days as late spring frosts are becoming less common after early May and Autumn extends well past September with very little frost happening until the end of October.This is great news for many plants but, certain traditional english crops such as rhubarb, blackcurrants and cherries, require a cold snap to tell the plant when to fruit .These plants could find future climatic conditions particularly challenging.

I was pleased to hear the RHS suggest the biggest concern for gardeners in the future will be water usage. It is certainly an issue that we all need to address by harvesting rainwater and recycling our grey water whenever we can – http://www.globalgardening.org/home/water and http://www.rhs.org.uk/advice/watering.asp.

The presenters mentioned two very impressive facts about our UK weather that I would like to highlight:

* 2006 was the hottest since records began in 1659

* 11 of the hottest years have been in the past 12 years

BUT THE BIG QUESTION FROM THE AUDIENCE WAS – WHY IS THE WEATHER SO BAD AGAIN THIS SUMMER?

It appears that the recent wet weather is due to La Niña. This is the opposite of El Niño which was apparently responsible for the hot, dry weather in 2006.

Climatic features in the equatorial regions of the Pacific Ocean off South America involve oscillations for water temperature with La Niña being associated with colder water and El Niño with warmer. The effects of these are felt throughout the world.

Although this year will be cooler than 2006 because of La Niña, it will apparently still be one of the warmest years on record as temperatures were much higher than normal at the beginning of the year. When El Niño comes around again in a few years, we should expect summer heatwaves again which will bring on the vines, olives and melons we are all starting to try and grow. However, this means that other more traditional crops such as brassicas and peas will need more watering.

That is the price we must pay for climate change. I would certainly rather grow melons than cabbages !