Bay Area Horticulture

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The San Francisco Bay Area is one of the major horticultural centers in the United States. Along with the Delaware River valley region of Philadelphia and Seattle’s Pudget Sound, the San Francisco Bay Area ranks as one of the top garden regions in the country. A rich tradition of amateur gardeners, botanical gardens, garden clubs, master gardener programs, plant societies, retail nurseries and horticultural institutions has developed throughout the counties that surround the Bay.

Unlike the east coast and midwest, the Pacific coast and the San Francisco Bay Area in particular, are blessed with an abundance of different climate zones. Because of our proximity to the ocean, the prevailing easterly flow of weather systems and a varied topography, there are several very mild and well-defined climate zones locally.

However, our Achilles heel is twofold. The first limitation is a lack of water as dramatized in our continuing droughts. Even in “wet” years most gardens require supplemental water. Our second weakness is the absence of a significant dormant season which many plants need to develop properly. Many of our perennials dream of growing in a Seattle or Boston garden.

Several plants are tricked by our mild climate into blooming at unusual times of the year. Classic examples are magnolias blooming in the fall and the annual Lobelia blooming throughout the year. Our fall color cannot compare to New England’s but a properly selected deciduous shrub or tree with abundant summer and fall water should perform admirably.

Our long growing season and mild winters also host several significant pests including aphids, fuchsia mites, mealy bugs, scale, slugs and snails, spider mites and the recent explosion of thrips. Occasional cold weather systems bring a hard freeze to our region, killing many tender plants and insect pests. The California Horticultural Society grew out of meetings evaluating the effects of the deadly 1932 freeze.

From this variety of growing regions came the Sunset Western Garden Book with its plant climate zone maps and plant hardiness ratings. There is no other gardening book quite like our homegrown “green bible.” Every Bay Area gardener should have a copy. Another valuable book for the home gardening library is Golden Gate Gardening by Pam Peirce, which is a complete guide to food gardening around the Bay and coastal middle California. Locally, Ortho has produced an excellent gardening reference book with its Ortho Problem Solver And no serious west coast gardener can be without “Pacific Horticulture”, the best regional gardening magazine in the country. Our San Francisco-based California Horticultural Society played a role in the magazine’s beginnings.

With the University of California Berkeley Botanical Garden and Golden Gate Park’s Strybing Arboretum, the Bay Area boasts two world class botanic gardens, each with an unique collection of plants. The Asian collection at Berkeley and the magnolias of Strybing are examples of the worldwide reach of each garden. Both gardens also play close attention to their local flora with significant native plant collections.

In addition we have the premier northern California native plant botanic garden located at Tilden Regional Park. Within the remnants of an old rock quarry, major collections of plants representing all the floral regions of the state have been assembled. The world’s definitive collection of manzanitas is gathered here. Gardeners interested in native oaks can contact the California Oak Foundation located in Oakland. Many natives and other ornamental plants are often planted in the fall because our mild wet winters and springs allow time for the newly planted out plants to become established before the following long dry summer.

At the southern end of the Bay Area, gardeners can visit the University of California Santa Cruz Arboretum, where one of the largest collections of Australian plants has been assembled. Excellent education programs in the new library/meeting room facility, plus the recently built gift shop, make this garden a hub for Monterey Bay horticulture. The Gardener’s Resource Guide for the Monterey Bay by Steve McGuirk and Richard Merrill lists every conceivable resource for gardening in the Monterey Bay Area.

We may not have a multitude of historic gardens as Philadelphia or Boston but we do have two landscape gems in Blake Gardens, located in Kensington, and Filoli in Woodside. Recently opened to the public, the Ruth Bancroft Garden in Walnut Creek offers three acres of cactus, succulents and unusual trees under the stewardship of the Garden Conservancy. The Hakone Japanese Friendship Garden in Saratoga has a Zen-style garden and a collection of Bamboo sponsored by a local Bamboo Society. In addition, the Bay Area supports several significant rose gardens in Berkeley, Oakland, San Francisco and San Jose. San Francisco also boasts Golden Gate Park, one of the great urban parks in the west.

A more recent phenomenon is the non-profit garden center. Two rising stars in this arena of public horticulture are the Heather Farm Garden Center in Walnut Creek and the Gamble Garden Center in Palo Alto. These centers serve their local communities with display gardens, educational programs and meeting facilities. On the shores of Lake Merritt, the Lakeside Horticultural Center offers meeting rooms, a composting exhibit, and the adjacent Lakeshore Trial and Show Gardens.

No gardening community can thrive without the resources of a strong horticultural library. The Helen Crocker Russell Horticultural Library at Strybing Arboretum is one of the nation’s finest. The library is open six days a week (closed on Tuesdays) for visitors to browse through its diverse collections.

When you are ready to start your own horticultural library you can find a wide selection of gardening books at: Black Oak Books, Builders Booksource, and the U. C. Botanic Garden Bookstore in Berkeley, ag Access in Davis, Bell’s Books in Palo Alto plus Strybing Arboretum Bookstore and William K. Stout Architectural Books in San Francisco.

Our local community colleges are involved in horticulture with programs in Los Altos Hills, Oakland, Pleasant Hill, San Francisco, San Mateo, Santa Rosa and Soquel. We do lack a four year or graduate degree program but U.C. Davis is close by. In addition, Strybing Arboretum, the U.C. Botanic Garden, and UC Santa Cruz Extension offer a wide selection of gardening classes.

South of San Jose, in San Martin, is the Saratoga Horticultural Foundation, a horticultural research institution responsible for many native and Mediterranean plant introductions. Their annual plant sales are good sources of unusual plants. Horticultural societies include the California Horticultural Society in San Francisco, the Western Horticultural Society in Palo Alto, and the Marshall Olbrich Society in Sebastopol.

Organic gardening and integrated pest management are very popular in the Bay Area. Several programs in home composting are offered throughout the region and the Bio-Integral Resource Center in Berkeley has a wide selection of publications for the home or professional gardener. SLUG, the San Francisco League of Urban Gardeners, fosters the use of urban spaces for gardening. Common Ground Garden Supply/Ecology Action Center is a peninsula hub for organic gardening supplies, information, and classes.

Spring begins with the San Francisco Landscape Garden Show. Soon afterward a multitude of local plant sales occur throughout the Bay Area sponsored by native plant groups, rose enthusiasts, orchid and begonia societies, and many more. Two of the largest Bay Area plant sales are the spring sales at Strybing Arboretum, San Francisco and Cabrillo College, Aptos (just south of Santa Cruz.)

Several seed companies are located in the Bay Area. Clyde Robins in Castro Valley, the Redwood City Seed Company and the J. L. Hudson Seedsman Company are both based in Redwood City. Spectacular summer flowering displays are open to the public at Goldsmith Seeds in Gilroy. A wide assortment of oriental vegetable seeds are available from Kitasawa Seed Company in San Jose. Not far to the north is Larner Seeds in Bolinas.

When you are ready to plant your garden a multitude of retail nurseries offer an incredible selection of plants. Two of the more unique are Western Hills Nursery (uncommon plants) in Occidental and Yerba Buena Nursery (natives) in Woodside. Where on Earth, A Gardener’s Guide to Growers of Specialty Plants in California, is a great book to keep in the car for nursery trips. While the book has been out-of-print for some time, it will be re-published this coming spring.

Some of the more comprehensive books on gardens in the Bay Area include Bay Area Garden & Resource Guide (1996) by the Master Gardeners of Santa Clara County, California Public Gardens – A Visitor Guide (1991) by Eric Sigg, Garden Getaways – Northern California (1989) by Nona Pierce, Glorious Gardens to Visit in Northern California (1993) by Priscilla Dunhill & Sue Freedman, A Nature Lovers Guide – California Gardens (1993) by Carol Leigh and Visiting Eden – the Public Gardens of Northern California (1993) by Joan Chatfield-Taylor. The Collector’s Garden(1996) by Ken Druse has several pictures of private/public gardens in the Bay Area and beyond.

We are indeed blessed with a multitude of plants, climates, gardens and plant enthusiasts. It’s an exciting area for gardening because of our long growing season and wide palette of plants for painting the landscape. Nearly every weekend there is an educational program, plant sale or special garden to visit. Take advantage of these offerings but be sure to leave some quality time for your own garden.