Together with its companion,
The Random House Book of Perennials: Late Perennials: 002 (Pan Garden Plants Series) this is the gardening book I use more than any other. Produced in the classic Roger Phillips style, it features superb quality colour photographs of an enormous range of perennials, together with botanical details, notes on growing, and, most useful of all, a description of their natural habitat. This is immensely valuable in judging whether a particular plant will survive in my garden, and where to plant it. For example, we are told of Cardamine pratensis (selected at random): " Native of most of Europe, to W Siberia and across North America, growing in damp meadows, by streams and in ditches" For the gardener, he adds, after giving height and flowering time "Very pretty, not invasive, and one of the best species for damp gardens, but may require protection from woodpigeons, which eat the young buds in spring. It is a host of the Orange Tip butterfly. The double form, 'Flore Pleno', has been grown in gardens since at least the mid-17th century". For me this is absolutely ideal, it tells me everything I want to know.
Where a plant has a lot of similar relatives, or where many garden cultivars exist, Phillips uses the tactic he pioneered, of photographing specimens like botanical illustrations, on a plain white background with a scale. Elsewhere, photographs are taken of the plant growing, either in a garden or in the wild.
The grouping is, as usual, by flowering time, which makes for the occasional anomaly, but the excellent index makes this little of a drawback. Plants are listed both by latin name and by "common" name, in the same sequence. An introductory section gives some interesting background facts and advice.