Landscaping with California Native Plants
Designing California urban landscaping using California’s native plants will conserve water, reduce chemical fertilizer and pesticide use, and decrease the risk of fire while helping save this unique flora. Most native species need very little water beyond the normal rainfall and require minimal maintenance because they are well adapted to California’s many climate conditions. In addition, native plants significantly decrease chemical pesticide use due to their natural adaptations and defenses against pests and diseases.
Conserving Water Using Native Species
California’s unusual weather and diverse topography have created a natural environment that is home to the most diverse plant life in the nation. More than 4,830 native species can be found in climatic zones that range from extremely dry to very wet, from coastal desert to alpine meadows. California’s native flora has evolved over eons to survive in the dramatic conditions that are the hallmark of the Golden State.
Southern California native flora withstands semi-desert conditions resulting in highly conservative water use. These plants can go two weeks without watering during the summer and up to eight weeks without watering during southern California’s brief rainy season. Compare this to the once or twice daily watering necessary for non-native plants such as Hibiscusrosa-sinensis (common hibiscus). California native species like Erigeron glaucus (Seaside daisy) are especially hardy and withstand abuse as well as drought.
Natural Pest Resistance
Most California native plants are insect and fungal resistant as well as destructive wildlife repellent. Native plants evolve under perpetual pressure from pests of all sorts including deer, rabbits, insects of various types, and disease. Each time the plant community develops resistance to a group of pests, the pests begin evolving to overcome that resistance. In this never-ending cycle of defend/defeat plants tend to maintain an upper hand. An excellent example of this is Dendromecon rigida (bush poppy), a flowering shrub that is both beautiful and deer resistant. Heteromeles arbutifolia (Toyon) is another good choice as a shrub, being both fire and deer resistant.
Should a problem appear, verify that it is pests prior to treating the plant. Many times horticultural habits better suited to imported tropical plants are the problem, not pests.
Water conservation and pest resistance are complimented by soil adaption. Soil in California varies from hard, compacted clay to decomposed granite to high salinity sand to rich loam. This soil diversity has resulted in native plants that grow in any type of soil in almost any climatic conditions, for example California native species Erigeron glaucus (Wayne Roderick Daisy) that grows in full sun in any soil including hard, compact clay soil. This adaptability significantly reduces the need for chemical fertilizers and the accompanying costs associated with those fertilizers. This, in turn, dramatically reduces the chemical pollutants in California’s oceans and waterways.
The 2003 Cedar fire brought southern California’s vulnerability to wild fire to world attention as 280,278 acres burned over the course of three days, killing 15 people, and causing over US$200 million in damages. Much of the area that burned was landscaped in non-native flora such as eucalyptus, Stipa capensis (Mediterranean steppe grass), and other imported plants. Had native plants been used instead of imports, the fire wouldn’t have spread nearly as fast or as far. Native flora is naturally fire retardant having evolved together with the frequent wild fires that burn through southern California’s coastal sage. In fact, many of these plants benefit from frequent small wild fires which disperse seeds and clear harmful underbrush. California native species such as Arctostaphylos densiflora (Harmony Manzanita) are considered highly fire retardant along with being extremely drought and pest resistant.
Water Conservation, Fire Hazard Reduction, and Lower Maintenance Costs
Using California native plants in urban landscaping makes good financial and ecological sense: Stingy water users by nature, California native plants utilize every drop. In a state that imports the majority of its water, proper utilization of this precious resource is paramount; native plant fire resistance makes worrying about California’s frequent wild fires a thing of the past; California’s varied topography and soil conditions force native plants to be efficient users of even the smallest amount of beneficial minerals and organic matter eliminating the need for chemical fertilizers; natural pest resistance eliminates the need for chemical pest control. Lower water usage and no chemical fertilizers or pesticides add up to much lower maintenance costs and help maintain a healthier environment.