Nicki Chapman and Angellica Bell have exclusive access to the long-awaited opening day of this year's RHS Chelsea Flower Show. On a VIP-packed press day, Nicki chats to Lisa Snowdon about her love of gardening, and James Wong hunts out the best houseplants. Frances Tophill tells you everything you need to know about building your own Insta-Pond, and Mark Lane takes a first look at the Great Pavilion.