My shelves are full of gardening-related titles that get used rarely. But there are a select few that are always within arm’s reach.

Michael Dirr

Michael Dirr, author of the most widely used books on trees and shrubs, speaks with students at Middlebury College in Vermont during a 2009 visit to the campus.

I’ve collected hundreds of garden-related books over the past few decades. My bookcase shelves are organized by topic: vegetables, fruits, trees and shrubs, perennials, herbs, travel and field guides, landscaping, water gardening, small-space gardens, xeriscaping, flower bulbs, pests and diseases, companion plants and weeds, lawns and more. All have been useful at one time or another, but most of them just insulate a wall of my office and collect dust.

A handful of them, however, stay at arm’s reach, ready to answer questions, give advice, or provide inspiration on a weekly or even daily basis. In my professional life as a garden center nursery supervisor, I use Michael Dirr’s Manual of Woody Landscape Plants every day as I help customers make buying and planting decisions. I’m willing to bet that nearly every garden center in the U.S. that sells trees and shrubs has a reference copy of Dirr’s manual, too.

I used the first edition of the manual as an undergraduate horticulture student back in the 1970s. After five revisions, this bible of woody ornamentals remains fresh and invaluable. The current edition, released in July 2009, tops out at 1,325 pages. It’s organized alphabetically by plant genus and species. To assist readers who haven’t memorized hundreds of scientific names, the book has two indexes: one by botanic name and one by common name.

“The manual”

The book’s clear organization and depth — plus Dirr’s opinionated and often humorous writing and expert recommendations — make this book truly valuable and accessible. He covers each species in depth, including most commercially known cultivars. Each species includes 19 topics, including leaf, bark, fruit and flower descriptions, major insects and diseases, growth rate, mature size and habit, hardiness, culture, propagation, native habitat, landscape value, and cultivars. Most species include pen-and-ink illustrations of the leaves and twigs for identification purposes.

Dirr’s Hardy Trees and Shrubs also makes my short list of most-used books. This one is filled with color photos of the author’s most recommended woody plants. Most are shown in landscape settings, making it easy to imagine how they might look in your own situation. One of the book’s finest features, though, is the section at the back in which Dirr includes nearly 40 lists of trees, shrubs, and vines categorized by specific uses. Looking for shrubs that tolerate dry soil, have fragrant flowers, or make good hedges? Need a tall, narrow tree or one that has great fall color? When I’m working with customers who have specific landscape challenges and requirements, this is the first book we consult.

Average gardeners may not need or want to own these books, but I think it’s important to know that they exist and that they’re readily available references at most garden centers. When you shop for trees and shrubs and want more information than appears on the tag, ask a salesperson to pull out their copy of Dirr’s book. Chances are they’ll have a tattered copy of the manual somewhere within reach.

I’ll be writing about more of my favorite gardening books and authors in future blogs. What books do you turn to year after year?

—Ann Whitman

Green Goods Supervisor, Gardener’s Supply