February 17, 2018
What happens when you plant bougainvillea and water it in summer? What happens when you plant foxtail agave in hot inland areas? What happens when you plant a citrus tree in your lawn area? Interested in these and other landscape issues? Read on to learn more about plant selection for Marin landscapes.
To select the right plant for the right place, start by understanding a plant’s usefulness in a variety of settings. Plants do best when we duplicate their natural adaptations to light, water and temperature. Because the Earth moves around the sun and because climate patterns often vary, before planting, one should check a plant’s seasonal water needs, light requirements and temperature ranges all of which determine whether or not a plant thrives where you plant it!
Marin’s Mediterranean climate gives us winter wet and summer dry conditions. When we select a landscape plant, we need to keep this a primary focus for selection. Plants adapted to this moisture cycle include many California native plant species as well as a large number of plants from the other four areas around the globe with Mediterranean climates, including the Mediterranean Basin, areas of South Africa, Chile and Australia. Other tips for success include aggregating plants with similar water needs, selecting plants that fit the space, determining the soil meets the nutrient and drainage needs of the plant, practicing integrated pest management and avoiding invasive plants. Follow these practices and you are likely creating and protecting wildlife habitat, improving air quality, conserving energy and reducing green waste.
To help you select the right landscape plant, there are several online guides, including marinmg.ucanr.edu (click on Selecting Plants), the online California Master Gardener Handbook and the online resource book “Landscape Plants for California Gardens” by Bob Perry who teaches landscape architecture at Cal Poly, the University of California at Los Angeles and the University of Southern California. This illustrated reference book classifies plants that need water regularly as IG 1 and plants that need reduced summer water as IG 2.
When should bougainvillea be watered? Bougainvillea, native to sub-tropical climate zones of South America, is selected and planted for its beautiful flowers. The plant has no tolerance for winter frost and thrives in full sun with low amounts of supplemental water during summer. Overwatering bougainvillea promotes foliar growth and reduces flower production.
What temperature conditions favor foxtail agave? Native to rock habitats of Mexico, foxtail agave is sensitive to frost. At 3 to 5 feet tall with its large, bold, blue leaves, this clumping plant requires low to very low amounts of supplemental water in summer when planted in coastal, protected areas. But, when planted in hot inland areas, it needs regular water or its pale bluish leaves will yellow and leaf tips will burn.
Where you plant citrus and how you water it matters. Native to Asia, and widely planted in areas that have frost-free winters and warm summers, their shallow root systems prefer regular water from winter through the end of summer. Citrus also prefer a space of their own to avoid competing with grass roots for water and nutrients.
Most often, we homeowners select a plant when we have a specific need or interest. We like an aesthetic look or have a specific need like lemons available not far from the kitchen door. Remembering to focus first on water needs, light requirements and temperature ranges helps insure the right plant gets planted in the right place. Success comes with preliminary research followed by careful execution.
Being a part of San Francisco Bay Area means Marin County experiences sudden variations within climate zones. Dense fog and cool maritime breezes give us climate conditions that depart from warm summer conditions prevailing in other Mediterranean climate zones. Pay attention to conditions needed for a healthy plant and you will reap the rewards of conservation and aesthetic character.