UCCE Master Gardener Program
of Humboldt and Del Norte Counties
Humboldt County Office
5630 South Broadway
Eureka, CA 95503
Phone (707)445-7351
Del Norte County Office
586 G Street
Crescent City, CA 95531
Phone (707)464-4711
Right Plant Right Place - Know Your Planting Zones
Successful gardeners know to have healthy and happy plants, is knowing how to select the right plant for the right place. Knowing your climate, sun light, irrigation and soil requirements for plants are the first steps in selecting the "Right Plant for the Right Place".
Many factors contribute to the success or failure of plants. Cold, heat, wind, soil type, soil moisture, humidity, pollution, snow, and winter sunshine can greatly affect the survival of plants. Placement of the plants in the landscape, the way they are planted, and their size and health might also influence their survival.
Light: Plants have various requirements for sunlight to thrive. Get to know your landscape and how the sun falls at different times of day. Keep in mind that buildings, trees and shrubs can shade areas in your landscape affecting sunlight exposure.
Soil moisture: Plants have various requirements for soil moisture, and this might vary seasonally. The type of soil whether it be clay, sandy or loam drains at different rates affecting the soil's water retention
Temperature: Plants have various cold and heat tolerances. Knowing your climate zone is extremely helpful.
Humidity: Humidity affects moisture loss from leaves. High relative humidity limits cold damage by reducing moisture loss from leaves, branches, and buds. Cold injury can be more severe if the humidity is low, especially for evergreens.
What are microclimates? Most all landscapes and gardens have microclimates. Microclimates are variations in your landscape or yard. Hardscapes such as blacktop and concrete—or cool spots caused by small hills and valleys create variances. Individual gardens also may have very localized microclimates. Your landscape whether it be sheltered or exposed can be different than the surrounding area. South facing walls can be warmer and low spots in your landscape can create pools of cold air.
DETERMINING YOUR PLANTING ZONE
The Western Sunset Gardening Zones takes into account the total climate - length of growing season, rainfall, the winter lows and the summer highs, wind and humidity. Your garden library would benefit with the latest publication of this book. Sunset Zone Information
The USDA Cold Hardiness Zone map is based on the average annual extreme minimum temperature during a 30 year period in the past, not the lowest temperature that has ever occurred or might occur in the future. USDA Planting Zone Interactive Map is a tool where you input your zip code and the map will indicate the cold hardiness zone. Go to Map
The AHS Heat Zone was developed by the American Horticulture Society to indicate the heat averages recorded by the National Weather Services for a twenty one year period.
Check out California Garden Web for more information on climate zones.