We visit the press launch for 2018's Chelsea Flower Show to discover the exciting gardens in store this year. Our trusty team of gardening experts answers questions on how to dig safely, keeping potted Christmas trees alive, whether you can grow houseplants in dark rooms, and what to do about a lawn that keeps dying. Plus botanist James Armitage unearths more horticultural histories in his latest Wisley Plant Encounter ( see www.rhs.org.uk/wisleyplantencounters ).