A one-hour special demonstrates how non-professional horticulturalists can lift design techniques from historic gardens, and visits Gloucestershire's Westonbirt International Festival of Gardens to see how even small spaces benefit from cutting-edge design. Presented by Chris Beardshaw . Director David Leighton ; Series editor Gill Tiemey BBC MAGAZINE: Gardener' World, £2.80; BBC BOOKS: Gardeners' World: Alan Titchmarsh 's Complete Book of Gardening, £12.99, from www.bbcshop.com Design principles: page 34; Wasp trap offer: page 35