Few of us that garden in the Sierra foothills were fortunate enough to have been born here. Most of us are transplants, non-native exotics (hopefully not too invasive), drawn here by the rugged rural beauty, the open spaces, and the small and friendly communities.
And most of us bring with us notions of the perfect garden, often based on gardens we have had or seen. Gardening in the foothills, however, is quite a bit different than gardening in many other parts of the country, and our gardening dreams and desires are often challenged by the realities of our climate and environment. In large parts of California, the moist air from the coast provides a moderating blanket that damps out climate extremes, provides a cooling effect in summer as well as reducing evaporative losses in plants and substrates. This effect is most noticeable along the coast, but extends inland to areas like Napa and even parts of the Central Valley. None of this moderating influence makes its way to the foothills. We are left high and dry, with not even a vestigial remnant of the marine influence to soften our summers. Our summers start early with temperatures of 100 degrees or higher occurring as early as May and continuing until October. No rain falls during this time. Winters are not severe, but are certainly not the mild and temperate seasons known in other parts of the state. Depending on the elevation, temperatures may occasionally drop into the teens with snow.
Learning to garden in such a climate can be an experiment in frustration unless one is willing to start over with almost no preconceived notions of what one grows in the garden and how one grows it. At a local MLRGS meeting, one new member from Southern California was moved to exclaim, " I feel like I have moved to Mars! " Mars, notably, is the planet of war, and some gardeners may feel that they are in fact waging war against the heat, the aridity, the gophers and the deer .
Take heart , gentle gardeners , and rejoice that it least we do not have banana slugs.
This is not meant to be a treatise on a foothill gardening, but the following are several tips that can help any gardener take advantage of the unique magic of our environment and climate.
1. Distrust almost anything you have read in any gardening book or magazine that is not dedicated specifically to our area.
2. No matter what types of plants you ultimately decide to grow--drought tolerant or thirsty--allow your plants to become established in the garden long before the heat of summer hits . This means planting in the fall when temperatures have started to cool, or in the very early spring. In my garden, at an altitude of about 2,000 ft. I typically begin my spring planting in February. Despite late hail and snowstorms, I have never lost a new plant to cold , but I have watched countless hapless victims wither away under the gaze of a hot spring sun.
3. Notice and take advantage of micro-climates created within your landscape. One plant can shelter another. A large rock placed next to plant will protect the roots from the sun's heat and slow evaporative moisture losses. Most of the rocks in my garden are placed there for reasons of survival, not aesthetics. Rocks are your friends!
4. Learn rock gardening techniques. The berms and mounds create the excellent drainage that foothill adapted plants demand. A gravel mulch provides insulation from the heat without compromising that drainage. (Join the Sierra Rock Garden Society to learn more.)
5. Look to California natives and plants from other areas of the world that share a Mediterranean or similar climate. We have done well with plants from the Balkans, and Turkey.