California
and Its Plants
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When it comes to natural features, California is a truly vast domain-larger and far more diverse than many countries of the world. This diversity begins with the land itself. There are spectacular ocean bluffs and terraces; row upon row of hills and mountains further inland; a huge and fertile central valley; the grandest and most scenic range of mountains in the Lower 48, the Sierra Nevada; and still further to the east, true deserts, parched yet teeming with life..
All of this helps to account for the 6000-plus plant species found within our borders. While a sizeable portion of these are too plain, too small or too specific in their adaptation to unusual soils and climates to be of interest in the garden, there are hundreds of showy and useful plants, as worthy of cultivation as many garden favorites from other regions of the world. Some have already been cultivated for a century or more, both here and abroad. A few are among the standard offerings of California nurseries. Many others are barely known and represent the frontiers of California horticulture.
Using Natives in the Garden
Too much that has been said and written about California native plants implies that they form a uniform category, distinct from other plants by their very origin. For example, it has been popular to lump them under the heading, "drought tolerant" or "low maintenance". With habitats as distinct as marsh and desert, plus all the smaller shadings of soil types, exposures and altitude, there must be major differences in the uses of native plants in the garden. Added to these are a huge range of actual plant types. We have large trees, like certain oaks, maples and bays, which will grow to dominate any landscape, providing understory habitats for many other, smaller plants, as they do in the wild. A number of foliage shrubs, like the wax myrtles (Myrica) and coffeeberries (Rhamnus) are useful individually or in groups of any size, including shrubby borders and screens. Many dazzling flowering shrubs-the wild lilacs (Ceanothus) are perhaps the most loved and appreciated-make bold and decorative displays anywhere. Around the shrubs and under the trees can go a vast array of beautiful herbaceous perennials and subshrubs. The smaller buckwheats (Eriogonum), heucheras and iris are some of the showiest and most familiar, but there are many more. California has grasses and bulbs galore for making meadows. For woodsy settings there are many exquisite native ferns and flowering plants like wood sorrel (Oxalis oregana) and wild ginger (Asarum). And there are plants for rock gardens and rock walls, pools and streams, and virtually any other setting the gardener might conceive.
Yet there are features of the California landscape, and of its vegetation over fairly large areas, that present a certain visual "flavor" and seasonal progression, quite distinct from that of the subtropics and moist forests which provide so many of our garden plants. Many dryland plants have small leaves for water conservation, giving them finer textures than more familiar exotics. Colors are often muted, and include many shades of grey, related to protective coats of hairs (another water-conserving feature). Flowering plants tend to make their displays from late winter-when they offer cheery relief from the bare-bark shades of many exotics-to late spring, when the soil dries and hardens. Summer and fall tend to be times of rest, though there are plenty of exceptions, especially among streamside plants.
Cultural Details
The diverse habitats and plant types that give California native plants many uses also make it impossible to prescribe a standard recipe for their culture. Just as one would need to know, not just the native country, but the actual habitat, of an unfamiliar exotic to grow it well, one needs to know where in California a given native plant comes from (though with both natives and exotics, there are plants with amazingly broad tolerances). Plants of coastal bluffs and meadows often need more moisture than those of similar settings farther inland, and they may not thrive in the high summer heat of the Central Valley. Many streamside plants require abundant moisture but are tolerant of a wide range of temperatures. Understory plants of the forests usually need some shading, all the more so as one moves inland (again, summer heat is a deciding factor). Yet the forest trees themselves are often more adaptable-coast redwoods and bays are good examples. Plants of the chaparral, the distinctive shrubby forest of exposed slopes, are often well adapted to heat and drought. However they may not tolerate typical garden-style irrigation in summer. Many have poor resistance to root pathogens that thrive in warm, moist soils. Watering technique can be all-important for these plants. Occasional, deep watering keeps crowns and branches dry most of the time, but provides sufficient moisture to maintain these plants in robust condition. In the hottest areas, it may be necessary to further reduce stress by light shading, particularly in the afternoon. This effectively lowers the temperature of both tops and roots.
Plants of hilly and mountainous regions are often found in rocky or sandy soils. It is a safe bet that most of these plants will require well-drained soils in the garden, again in the interest of disease control. "Flatlanders" cursed with dense, clayey soils need not despair, however. Planting on raised mounds and berms is often more effective than expensive soil amendment in draining water away from sensitive crowns.
These are the reasons that cultural details are given below for each genus, and in some cases, for each species of more widely distributed genera. Yet exactly the same details are provided for non-native plants in our Guide to Ornamental Plants for Coastal California. They are no less important for a plant from the highlands of southern Mexico or the coastal plains of western Australia than for plants of rocky hills in California.
California Natives and Suncrest Nurseries
Suncrest Nurseries draws on two traditions of enthusiastic native plant trials and introduction. The first is that of Leonard Coates Nurseries, founded in 1878 and occupying our present site from 1969 to 1990. I had the good fortune to take an active part in native plant introductions at Leonard Coates during the 1970s, and to continue and expand these efforts at my own nursery, Wintergreen Nursery, from 1978 to 1991. This formed a second tradition, absorbed with the sale of Wintergreen to Suncrest at the end of 1991. We have continued selections in the wild since that time for Suncrest, as well as drawing on the efforts and experience of friends at several botanic gardens and nurseries and dedicated private gardeners. The descriptions which follow should reveal just how broad the scope of those collective efforts has been. It is our great pleasure to serve not only as an original source but also as an enthusiastic conduit for promising native plants of all categories and genera.
Plant Descriptions
The descriptions which follow are largely self-explanatory. Each one attempts to provide not only a sketch of important plant features but also reliable details of successful culture. Remember, however, that the rules change a bit as one moves from the coast, where cool summers place little water stress on plants, to the hotter interior. "Occasional" watering may mean, for the coastal gardener, monthly or less, while twice that frequency might be required in the Central Valley. In the latter case, shading may also be needed, as described above. Plant hardiness is given in terms of minimum degrees Fahrenheit that a plant has been observed (in some cases, is simply assumed, from its placement in the wild) to endure for short periods without major damage. These estimates are generally conservative, incorporating actual experience in some brutal freezes.