At Longmeadow, Monty Don makes plans for the summer by starting dahlias and other tender perennials and sowing annual climbing plants hoping to light up his borders with colour. Adam Frost heads to Dorset to meet a tropical plant enthusiast who has filled his small back garden with unusual and rare exotic plants, many of which he has grown from seed. Plus, a visit to a garden in the Isle of Wight, which is filled with daylilies. Includes Weather.