'Kevin McCloud had two Grand Designs shows this year, one in London and one in Birmingham. The Grand Designs people had already had an approach from Christian Aid and asked if that would be OK.  I had seen the garden Claire Whitehouse had designed for Christian Aid at Hampton Court two years ago and was greatly impressed by it.

Grand Designs Live is a lot about material living, and so it's good to step out from that and see something that isn't about that.'

'Everybody, I think, is concerned about it at the moment. From George Bush talking openly about the Kyoto protocol and Al Gore making a movie, down to it being a local issue – this year I couldn’t used hosepipes on my garden – then it really brings it home how many people it affects.'

I was invited to research the kind of organic farming in Africa which makes up the Eco Garden. Even though I had a lot going on in the office (Diarmuid is a garden designer as well as TV presenter) and at home (he also has a 21 month-old daughter), when you’re offered something like this, you have to do it.'

'In a country like Kenya, where there are not many ways to make money on a big scale, the big message I took back from my trip was how people are making progress. The people I met are the same as you and I...people like Damaris Ndunda.

'I saw several organisations supported by BIDII (Benevolent Institute for Development Initiatives) a partner which Christian Aid funds. Many were concerned with soil and water conservation. The multi-storey garden where gardens are planted in tiers so that the water runs through each level and isn’t wasted, compost manure which preserves the earth and terraced gardening which meant that the water didn’t run down the hills and wash away all of the soil causing erosion. They were all great ideas, and they say the best ideas are the simplest. That was true of much of what I saw in Kenya.'

Because of climate change, droughts and floods are happening more frequently. They used to happen once every 15 or 20 years. It’s now more like every four or five years, and that makes planning for natural disasters is getting harder when it should be getting easier.'

'No. I'm not a big political campaigner. In Ireland, I front a massive campaign for recycling but at home my wife does all the recycling. I'd just like to convey the message that simple solutions work. In a country like Kenya, where droughts are a real issue, it makes me hopeful that people are using agriculture to take on changes to the climate in ways that are going to work. This affects all of us on the planet.'

'I was told 25 years ago at gardening college to use certain pesticides. I never fell for it then and I don’t fall for it now.'

'People can have a greater awareness of how to conserve water, not using artificial fertilisers which are bad for the environment and bringing your own supermarket bags when going shopping. That is a massive change from ten years ago. An issue like this a decade ago was seen as a ‘lefty’ issue for people with beards and sandals. That’s not true anymore. Parents are much better informed and an issue like this will always start with children changing first.'