This book has a similar philosophy and arrangement by cultural conditions as Penelope Hobhouse's Natural Planting. While Hobhouse looks to gardens around the (temperate, Western) world, this book is all based on Beth Chatto's garden. But that's enough, as these are the large and varied display gardens at her retail and commercial nursery. The gardens are set in Essex, an area of England with harsher conditions (drier year-round, with a cold winter) than most of the country, and thus more like that of much of North America. While the book doesn't have a big alphabetical plant reference in the back, Chatto does have a few pages on each of many of her favorite genera. All of Chatto's books are worth purchasing if they match your local conditions (e.g., The Damp Garden, The Dry Garden).
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