Perennials are the basis of virtually every garden. The shelves are loaded with books that give readers the same list of plants. That “encyclopedia” is missing from this book — who needs another one? Instead, Bill Cullina has offered what he describes as the psychology of perennials — their needs, wants, and potentials. Starting at the roots, moving up through the stems, the leaves, and finally the flowers, Cullina’s book stands as the definitive word on the horticulture of the most important plants in everyone’s garden.