Rachel De Thame sharpens her shears to champion topiary, the great tradition of trimming and shaping plants. Rachel charts the rise and fall of topiary from Elizabethan times to the present day, meets a topiary-obsessed woman in Kent who has transformed her entire garden using amazing topiary creations and witnesses the hedge handiwork of a man in north London who is causing a buzz in the local neighbourhood with his living sculptures. Rachel shows that, with a little know-how and confidence, everyone can share in the sense of fun that topiary can bring to Britain's gardens. James Wong, meanwhile, is up on the roof. He uncovers the hidden horticultural past of the capital's rooftops, visits a woman who has moved her entire garden to her rooftop apartment and heads to Birmingham's new city centre library with an innovative rooftop addition. James shares his tips and shows us that, when it comes to roof gardens, containers are king. He also reveals the best plants that are...