You'll find a dog-eared copy in just about every local nursery and plant store, and landscape designers use
Sunset Western Garden Book also for any and all useful information on over
10,000 species of plants. This information includes growing traits, the likes
and dislikes of the plant (e.g. likes full sun, is drought tolerant, etc.), the
size of the plant at maturity, and just about anything else you can think of
needing to know.
This isn't the type of book that you'd read cover to cover, but if you use it as a reference book, it could save you from making a costly mistake! The information is broken down by climate zone. The book contains excellent maps so you can see what plants will thrive in your area and which won't last long. This alone can save you a lot of money when selecting your plant material.
Whether you are a novice or a master at gardening in the West, this is the one book you CAN NOT be without.