California climates may be cool enough for apples, and warm enough for subtropical ornamentals like A Phormium varieties; B Abutilon ‘Kristen’s Pink’; C A. ‘Fool’s Gold’; D Dodonea viscosum ‘Purpurea’; E Abutilon ‘Seashell’; F A. ‘Kristin’s Pink’; G Phormium varieties; H Coprosma ‘Roy’s Red’; I C. ‘Pink Surprise’; J giant redwood Sequoiadendron giganteum ‘Hazel Smith’.

 

Gardeners in Coastal California think that their climate is so special, so unlike the rest of the country that they have little in common with people who tend the soil elsewhere: And they are right. Gardeners west of the Rocky Mountains even have their own growing zone map based not on the climate zones determined by the United States Department of Agriculture, but on twenty-four divisions established by Sunset Magazine.

These gardeners face significant challenges: mudslides in winter, low rainfall in summer, earthquakes, and wildfires.

Despite those impediments, California is a gardener’s paradise. With warm, sunny hillsides, Californians can grow a host of plants from Australia, South Africa, and the Mediterranean: figs, olives, citrus, walnuts, and of course, wine grapes. The climate is also ideal for invasive exotic plants, which have overrun many of the state’s some 5,000 native trees, shrubs, grasses, annuals and perennials, bulbs, and herbs. The situation is not quite as dire as it is in Hawaii, which could stand as a warning.

The best gardens to house the myriad exotic, noninvasive plants might be urban plantings. These mini-botanical gardens could be thought of as zoos. Imagine a place like Berkeley in the East Bay across from San Francisco where it is warm enough to grow some citrus and bananas, but cool enough to have a few lilac varieties and apples. There are succulents: agave, aloe, tropical aeonium, and echeveria. You can see palms there and clumping bamboo. There are the immensely popular strap-leafed New Zealand flax (Phormium varieties related to lilies), the horsetail-like “restios,” and the more familiar fuchsia, jasmine, confederate jasmine (Trachelospermum jasminoides), tree ferns, and flowering maples (Abutilon varieties). Abutilons, related to hibiscus, have nodding flowers and species coming from Central and South America, China, India, California, and even Hawaii.

If I had land in California, I might try to grow native plants like the late-winter-blooming Garrya spp. with flower tassels that look almost like icicles, coastal redwoods, Douglas iris, flannel bush, and others in the outer areas of the property, while keeping more tender exotics closer to the house. California native plants may be recognized for specific epithets like californica, occidentalis, douglasii, or fremontii.

For those who garden up the coast in Oregon and Washington State, the climate resembles Great Britain’s. I have to admit a bit of environmental jealousy toward folks who can grow the plants we see in English books and magazines.

In a Berkeley garden by Brandon Tyson: Brahea armata (Mexican blue palm), coral flowers of Aloe distans, and rosettes of Echeveria imbricata.

Bob Clark’s Oakland, California, garden combines art with horticulture. The climate—neither too cold nor too warm— allows for plants that are cold hardy like pink flowering cherries, and ones that are frost tender like yellow angel’s trumpet (Brugmansia sp.) with huge, flaring flowers.