Learning to identify plants by family is a really good way for a gardener to get a handle on plant ID. It gives you a head start on understanding all sorts of things about a plant. It makes it easier to learn the plant's name, if you don't already know it, gives clues about how to grow it and propagate it. You will start to organize your knowledge of plants in very useful ways.
Next week I'll be teaching some California Master Gardeners to identify 5 plant families. For my students and others who are ready to learn more about plants, the following list of books and a web site will be of help. They offer descriptions and illustrations of plants in different families, as well as explanations and drawings to show the meaning of botanical terms.
I should also say that this is the second of two talks on the subject I can present to interested San Francisco Bay Area audiences. Each covers 5 families, includes a Powerpoint slide show and an extremely useful handout, and takes about 1 3/4 hours to present. If you might like me to give one or both talks to a group of gardeners, you can send me an email through my website, pampeirce.com,
Flowers are central to plant ID. A rose is known by its five sepals and petals, many stamens, and single pistil. In a double-flowered rose, many or all of the stamens have been replaced by petals.
Here are resources to help you learn more:
The Botany Coloring Book, Paul Young, Jacquelyn Guiffre, Harper Perennial, 1982. Learn plant anatomy and terminology through coloring the illustrations.
Botany in a Day: The Patterns Method of Plant Identification, Thomas J. Elpel, Hops Press, LLC, 6th Edition, 2013. Learn to identify plants based on plant family patterns. Covers eight common families.
Plant Identification Terminology: An Illustrated Glossary, James G. Harris, Melinda Woolf Harris, Spring Lake Pub, 2001). Twenty seven hundred definition, nineteen hundred illustrations.
Seed to Seed, Suzanne Ashworth, Seed Savers Exchange, 1991. Food crops, listed by plant family, with discussions of pollination and seed saving.
The families of flowering plants, L. Watson and M. J. Dallwitz. Descriptions and illustrations for the plant families. Includes an interactive key for plants and a set of botanical poems by Giles Watson. The link to this web site is: https://delta-intkey.com/angio/ or use this link: Families of Flowering Plants
Often, plant descriptions in gardening books will include the name of the plant family to which a plant belongs. For example you will find plant families listed in the Sunset Western Garden Book and in Golden Gate Gardening. If you want to know what other plants are in this family, try looking it up on the Watson & Dalwitz site, or try Googling the scientific name of the family. Wikipedia has articles on each plant family and you will find other useful sites.