The thing with gardening is that if you have a few goes at it and it turns out really badly, you just think you can't do it. When you have a space with little light, it's so easy to see something you love but you have no idea that it needs eight hours of full, hot sun and [so] it dies. So you assume you haven't got 'green fingers'. It's like when you see some people who are naturally good cooks – they throw everything in and they've obviously got an instinct for it. But you can still cook if you just read the recipe and buy the right stuff and I think it's the same for growing. Some people might be better at it than others but it's so easy to be put off. And it can be hard to see how you can green up spaces like balconies because they're so un-green and made of steel and glass and concrete.