Magill's Encyclopedia of Science, Plant Life [electronic resources] by 
The American Horticultural Society Encyclopedia of Plants and Flowers by 
A to Z Encyclopedia of Garden Plants by 
American Horticultural Society Encyclopedia of Gardening by An essential volume packed with authoritative advice for all gardeners, The American Horticultural Society Encyclopedia of Gardening guides readers expertly through the latest gardening techniques, details information on garden planning and design, and covers useful tools and materials.
Dirr's Hardy Trees and Shrubs by 
Plant Families by Most of us lump plants together in one big family, and when pressed can only explain their grouping by what they're not--not an animal, not a mineral, and so just a plant. In reality, there are hundreds of different plant families, each grouped logically by a unique family history and genealogy. This brings sense and order to the more than a quarter of a million different plant species covering a diverse spectrum that includes soaring sequoias (Cupressaceae), squat prickly pear (Cactaceae), and luxuriant roses (Rosaceae). Plant Families is an easy-to-use, beautifully illustrated guide to the more than one hundred core plant families every horticulturist, gardener, or budding botanist needs to know. It introduces the basics of plant genealogy and teaches readers how to identify and understand the different structures of flowers, trees, herbs, shrubs, and bulbs. It then walks through each family, explaining its origins and range, and describing characteristics such as size, flowers, and seeds. Each family is accompanied by full-color botanical illustrations and diagrams. "Uses For" boxes planted throughout the book provide practical gardening tips related to each family. We have much to gain by learning about the relationships between plant families. By understanding how botanists create these groupings, we can become more apt at spotting the unique characteristics of a plant and identify them faster and more accurately. Understanding plant families also helps us to make sense of--and better appreciate--the enormous biological diversity of the plant kingdom.
Stearn's Dictionary of Plant Names for Gardeners by 
The Tree Book: superior selections for landscapes, streetscapes, and gardens by "A boon to all those who plant, care for, and love trees."--Nina Bassuk, author of Trees in the Urban Landscape The Tree Book is the go-to reference to more than 2,400 species and cultivars, from two of the biggest names in horticulture--Michael A. Dirr and Keith S. Warren. The featured trees include those widely available in the nursery trade, some new and promising choices, and a selection of overlooked options that deserve renewed interest. Each tree profile includes the common and botanical names along with details on foliage; flowers, seeds, fruits, and cones; native range; adaptability; and popular uses in landscapes. The Tree Book is a must-have resource for landscape architects, city foresters, horticulturists, and enthusiastic home gardeners. 
The Visual Encyclopedia of Garden Plants: a practical guide to choosing the best plants for all types of garden, with 3000 entries and 950 photographs by This is the perfect sourcebook and reference manual for anyone building a garden plant collection and looking for inspiration and practical advice. It contains descriptions and essential cultivation information for over 3000 common garden plants. Entries are arranged alphabetically within plant categories for quick and easy reference. It includes essential advice on choosing plants for different soil types and garden locations. It is aimed at everyone from the new gardener to the experienced plant-selector.
