Summer gardening and the secrets of seeds

Seed saving can be a powerful and life-affirming act – permaculture designer Poppy Okotcha shares her thoughts on how and why we should all be saving our own seeds. Resident gardening guru Leigh Hunt dispenses timely gardening advice with his top 10 jobs for August, and RHS advisors discuss rain gardens. Plus: how long can seeds and plants last? Dr Chris Thorogood of Oxford Botanic Garden reveals some surprising facts.