Chris, Lottie, Trevor and Sally explore Birmingham's hard shoulders and soft verges, and discover how Danish scurvy-grass has become the fastest moving plant in Britain
The team see how a military no-go zone provides the perfect conditions for things to grow. Using explosive stunts, they explore how wild plants have developed their own defence systems to survive.
The team visit London, where they discover that the chewing gum on the streets is actually a living organism, and find out about the Amazonian plants attracted to the capital's alleys
In Snowdonia, Chris and the team examine the danger wild rhododendrons could spell for our countryside, search for threatened juniper berries, and find a rare British rainforest
