HE may be a household name in Britain since making his way to the Chelsea Flower Show with loose change in his back pocket 20 years ago, but Diarmuid Gavin is unknown in East Africa. At least, he was until now — a recent visit to Kenya changed all that.

You can picture the scene. The villagers of Kathian, two hours outside Nairobi, do not recognise their visitor from his prize-winning work at Chelsea, his many BBC gardening programmes or even his stint on Strictly Come Dancing. As they chant, clap and sing, their excitement is not due to Gavin but what he has opened — a new spring-water well. A concrete stone with his name and the date on it is next to the tap. It has been a long dry summer in Kathian, and drought, because of climate change, is more common than it was.

“We are so grateful that we now have clean water,” says Margaret Kisilu, head of Bidii, the partner organisation, funded by the UK-based charity Christian Aid, that was responsible for the well. “Before, the water came from the holes in the ground. It was getting contaminated and people were getting sick. Dogs were drinking from the same water as the people. Now 400 households in the community will have access to clean running water. With the shadow of more drought, this is invaluable.”

For people in the UK, conserving water, recycling and even returning their supermarket bags is evidence that the environment is being taken seriously. For Kenyans, the environment is more immediate. Natural disasters, like droughts and floods, which used to occur every two decades, are happening more frequently. This year an estimated 11 million East Africans were at risk of starvation because of drought.

Gavin was visiting the gardening and water conservation projects in Kenya as background for the Global Garden he has designed at Grand Designs Live. The exhibition at the NEC, Birmingham, aims to show how people in Asia, South America and Africa are changing their lives to deal with climate change. “The show features plenty about material living, and so it’s great to step out and see something which is about something beyond that,” said Gavin.

He was especially inspired by Damaris Ndunda, a mother of five, who started organic farming with help from Bidii. “Now she has 140 citrus trees and has enough for her family, with the rest of her produce going to market and to help the villagers.”

As well as the Global Garden, Gavin has fronted a campaign in Ireland to recycle plastic bags. His decision to appear in an advertisement for peat-free compost led the BBC to drop him from this year’s coverage of the Chelsea Flower Show because of its rules on advertising. “I’m not a politician, I’m a gardener first and foremost, but using organic materials is important to me, as it is for Alan Titchmarsh and Monty Don. We just don’t like to shout about it. When I was at gardening college 24, 25 years ago, the instructions were always: ‘Use this pesticide, use that pesticide.’ I never fell for it then, I don’t believe it now. I don’t understand why, to be a gardener, you have to put a mask on.”

There are similarities between Jamie Oliver and Gavin. Both were seen as the “rock’n’roll” answers to cooking and gardening when they emerged on British television in the mid- Nineties. “Whatever you feel about Jamie Oliver, you can’t deny what he’s done for children’s meals is brilliant,” Gavin says. “We have only just been learning in the past few years what is in food, and it was very obvious to me that we can learn from the sustainable farming I saw in Kenya.”

Gavin and his wife Justine (“she does all the recycling”) take this commitment seriously. “When our daughter was born 21 months ago, I made a rather grand point of saying: ‘I don’t want her eating anything that’s not organic.’

“My wife turned round and said: ‘Diarmuid, we’ve been doing that for years . . .’ ”

Especially after his trip to Kenya, Gavin’s interests go beyond the earth he works with and to the future of the planet itself. “An issue like climate change was seen ten years ago as lefty, the preserve of those with beards and sandals. Parents are much more informed now than they were ten years ago and kids aren’t stupid. Once people get over any issues of guilt, they’ll realise they can do something.”





Grand Designs Live runs at the NEC, Birmingham, from October 6-8
For Christian Aid’s climate change work, go to www.christianaid.org.uk/ecohouse

Times recommends

• Second homes: credit crunch casualty or money-spinner?
• How I built my own sliding house
• Top 10 incentives for house buyers