There's been a huge surge of interest in houseplants over the last couple of years, so Frances Tophill and Nick Bailey celebrate the joys of indoor gardening in a special programme from Oxford Botanic Garden.Rachel de Thame visits a nursery in Devon which specialises in growing the ever-popular orchid. We meet an interior designer in London, whose use of houseplants at home has allowed him to reconnect with nature. A self-confessed plantaholic gives us a tour of the indoor jungle he's created at home in Worcestershire, and we meet a gardener in Manchester who gardens on his balcony 18 floors up.We also look at the latest trends and must have houseplants of the moment, giving the best practical advice on how to care for houseplants and showing how to grow your own for free.