In my first job out of college, I was lucky and proud to work on an upcoming edition of the Sunset Western Garden Book. In the works for more than five years, the book that was finally published in 1967 turned out to be a groundbreaking guide to the West’s exploding plant palette and its highly localized plant climates. The book went on to sell millions of copies in various editions, including the latest in spring 2012.
The 1967 book was ahead of its time in the way it was produced—empirically and collaboratively. Today we’d call it crowd-sourcing.
Sunset magazine’s garden editor Joe Williamson, who headed the book’s development (and also was deeply involved with Pacific Horticulture in its early days), hired me to help out with the book’s climate section. He said he hired me because I knew what UC soil mix was—an esoteric bit of knowledge among English majors and the only thing I had learned from a summer job of shoveling and lifting at a wholesale grower of fruit trees and California native plants.
I remember Williamson worked with an artist to draw climate-zone boundaries on big sheets of tracing paper on a plywood-on-sawhorses table. He started with data from UC Davis climatologists who were mapping California’s agricultural climates—the same revolutionary research that guided wineries to new areas where wine grapes could be grown such as Santa Barbara and San Luis Obispo counties, not historically wine country, but now home to 44,000 acres of vineyards. But translating scientific research to what would actually grow in backyards called for on-the-ground exploring as well.
Williamson assigned me to map the range of California’s digger pines—an old and politically incorrect common name for Pinus sabiniana, named after the local Native Americans who were considered to be diggers of grubs and roots but whose varied diet actually included venison, fish, and berries. He considered that rangy, grayish pine to be an indicator of the climate that would become Zone 7 in the book, defined as having hot summers and mild but pronounced winters, without severe cold or enervating humidity—good for plants that require distinct seasons to flourish like peony, lilac, and flowering cherry. Determining the range of the pines meant driving my no-frills, stick-shift Chevrolet Biscayne through their heartland, California’s foothill Gold Country. As far as I was concerned, the main indicator of the region’s dry, rocky hills (beautiful in spring!) was the rattlesnake, and I rarely left the car except to call on forestry stations, nurseries, and firehouses to make notes on their weather records. I returned with enough data for Williamson to draw climate-zone boundaries on his map: Climate Zone 7 included towns straight out of Mark Twain like Angels Camp, Rescue, Copperopolis, and Shingle Springs.
Creating localized climate zones was part of Sunset’s mission to provide Western homeowners with specific how-to gardening advice for a region that was different from the rest of the country in geography, weather, lifestyle, and attitude. National shelter magazines of the 1950s and ’60s lacked coverage of the booming West’s new subdivision homes in need of landscaping, the whole new palette of plants coming in from Australia, Asia, and South Africa, and the emerging outdoor lifestyle that included essentials such as patios, overhead shelters, pools, and barbecues.
Climate advice coming from national garden books and magazines also wasn’t serving the West well. The complex nature of the Pacific Coast climates, influenced by proximity to the ocean, flow of air currents, and weather-affecting north-south mountain ranges near the ocean and inland, created a set of variables that defied the U.S. Department of Agriculture’s widely used plant hardiness zones. Based on minimum low temperatures, the USDA system created such anomalies as Tucson’s saguaro desert and Washington’s Olympic rain forest in the same climate zone. (Revised USDA hardiness maps, released in spring 2012, are more targeted and useful for westerners.)
The 24 proprietary climate zones Sunset developed for the 1967 book took into account other factors beyond minimum temperatures such as heat, aridity, rainfall, and fog, which determine where plants can grow. The zones were detailed enough to distinguish between thermal belts that rim the Central Valley (Zone 9)—mild enough for citrus groves—and the abutting, colder, lilac-friendly Zone 7.
No one told me that my snake-fearing trip through the Gold Country was part of an innovative effort to research and create plant climate descriptions in a new way, based on observation rather than theory. Leave it to a grad student who came along later to explain it.
Ben Logan, in his 2006 master’s thesis at Virginia Tech, wrote: “Sunset Magazine developed a purely empirical set of Garden Zones … The Sunset Garden Zones are well recognized and respected in the western states for illustrating the several factors of climate that distinguish zones… Gardeners and horticulturists turn for guidance to the Sunset Western Garden Zones, a more complex taxonomy of climate built on several variables, rather than on a single one”—a reference to winter low temperatures as the USDA’s sole climate zone determinant.
Similarly, the 1967 book’s 277-page plant encyclopedia was developed empirically and collaboratively. Specific climate-by-climate plant descriptions and evaluations of plant performance came from expert collaborators in the 13 western states that Sunset served. Dozens, maybe hundreds, of nurserymen, landscape architects, botanists, and extension agents contributed.
A regular gathering of Sunset’s “LA Panel” provided special input for Southern California. Monthly or so, a group of the area’s horticultural and landscape intelligentsia were invited to the Jonathan Club, an old-school, males-only spot in downtown Los Angeles to drink Old Fashioneds, eat New York steak and Crenshaw melon, network, and answer questions posed by the magazine’s editors gathering regional expertise. Landscape architect Morgan “Bill” Evans dominated. It’s hard to say how much of this was due to his powerful presence (I swear he was as tall as a California fan palm and had a mustache as broad as a patio broom) and how much to his horticultural accomplishments; Evans worked closely with Walt Disney to turn Disneyland into a living demonstration of Southern California’s subtropical potential. Santa Monica garden designer and all-around plantsman Phil Chandler was never wrong. L. K. Smith of Thousand Oaks, at the far edge of the expanding LA megalopolis, looked out for the practical interests of suburban homeowners and their bare 8,000-square-foot lots, hybrid Bermuda lawns, and patio overheads. Francis Ching, of the Los Angeles State and County Arboretum, contributed his Hawaii-raised knowledge of tropicals. Input from the panel gave the book a strong Southern California foundation at a time when interest in subtropical plants was cresting. They also helped pin down 12 climate zones in Southern California—probably America’s most climatically complex region where the frost-free coast, inland valleys, mild low desert, extreme high desert, and snowy peaks are all found within a hundred miles.
Dick Dunmire, also an active supporter of Pacific Horticulture, served as editor of the encyclopedia and continued to work on revisions of the book through 2001. To compile the encyclopedia, Dunmire collected information from the LA panel along with other consultants and other sources. He wrote a great many of the plant descriptions, drawing on Sunset magazine’s archive of garden articles, trusted manuals and books, and his vast memory of the plants he sold as a Bay Area nurseryman. Dunmire wrote the text in longhand, an assistant typed it, and copies from a Bruning copy machine were mailed to “checkers” (sometimes dozens of them for complex genera), who mailed back corrections and modifications based on their firsthand knowledge of plant performance, size, requirements, local adaptation, and other attributes. Dunmire and Williamson adjudicated the comments and modified the plant descriptions.
Regional feedback ruled. When an LA panelist disagreed with Dunmire’s text, Williamson deferred to the man on the ground. Dunmire told me recently: “Joe would say, ‘You’re from Kansas, do you think you know more than a guy who lives in Southern California?’” Williamson, known for his benevolent crustiness, was as chauvinistic about Western plants as he was about climates. The worst thing he could say about a plant was that it was a “New Jersey Plant”—which meant it could grow anywhere in the country. Why grow an elm or a spiraea in Santa Rosa or Covina or Eugene when you could grow Eucalyptus ficifolia or Daphne odora?
Updating a classic
A revised edition of the Sunset Western Garden Book has been published every decade or so. The 2012 is the ninth; its predecessors date as far back as the 62-page pamphlet-sized Sunset Garden Book of 1932. The 768-page current edition includes an encyclopedia with about 9,000 species and cultivars, a thousand of them new to the book. More than 2,000 color photos of each of the book’s genera replace the line drawings of the past few decades.
The new book was developed by Sunset staff members for a division of Time Inc., the owner of Sunset since the company bought it from the Lane family in 1990. Kathleen Norris Brenzel, Sunset’s garden editor since 1981 and the editor in charge of the Western Garden Book since 1995, says she has always thought she had to be “very careful with the book” because of its long tradition and reputation for usefulness and authoritativeness. Like the 1967 book, research for The New Sunset Western Garden Book began with a panel of experts including nursery growers, horticulturists, and landscape architects. What made it into the new book offers interesting clues about today’s gardening tastes and challenges.
More space is devoted to Mediterranean, native, and other drought-resistant plants introduced in the last decade. The editors cut back on roses, camellias, and rhododendrons—longtime favorites deemed of lower popularity now because of their higher maintenance demands. The 1967 book included 50 (!) species of eucalyptus covering eight pages as new imports from Australia flooded California nurseries; today’s book edits the list to 21 eucalyptus species and takes up a little more than two pages.
The book’s trusted climate zones have been revised to keep up with refinements in climate data and plant knowledge. Jim McCausland, a former Sunset staff writer who updated the climate pages in the newest book, cites reasons for the changes: As the West has filled in, there are new population centers in need of specific climate advice and more knowledge of what grows in areas such as Antelope Valley, north of Los Angeles, or Bend, in eastern Oregon.
McCausland also points out the new book’s continuing use of empirical, collaborative research: “In the book’s eighth edition, we had much of California’s Mojave Desert designated as Zone 10,” which is at a high altitude, with enough winter chill for lilacs, and enough summer heat for chile peppers. But we got sharp dissent from garden club members in the China Lake/Ridgecrest area, who said, ‘You have our zone wrong,’ and nurseryman Dan West in Hesperia. After exchanging emails and letters with those local constituencies, we changed most of the area to the less extreme Zone 11 for the ninth edition, and in fact moved Zone 10 out of California altogether.”
Sounds kind of like the collaborative, on-the-ground research we did in the 1960s. I wish I could have relied on emails instead of my Chevy Biscayne when we needed to determine the climate boundaries of California’s snake country.