It was March 2000 and I was with my friend Paul in the Darién Gap on the Panamanian-Colombian border looking for rare plant species. We had just entered a clearing with our two Colombian guides. For me as a gardener, it was the most amazing place. Suddenly several teenagers appeared brandishing guns – they threw us to the ground and tied us up. Our guides were dragged off into the bushes; we never heard from them again.

Our captors interrogated us for several hours, accusing us of being variously CIA, drug-runners and British spies. I kept telling them that I was a gardener looking for orchids and Paul was a mountaineer, but they wouldn’t have it. That was the beginning. For the next nine months we were held hostage in a series of camps on the border. In many of them I built a garden, just to keep myself sane; I’d plant a vegetable patch or grow some corn. They often threatened us, giving us the odd kick or punch. They couldn’t speak English and conversation was restricted to us thanking them for the armadillo we had for supper.

They made us write ransom notes to our parents – they wanted $5m. But they had no means of communication with the outside world so the notes were never sent.