What is Your Climate Zone?
The best overall description of the climate zones in Marin County can be found in the Sunset New Western Garden Book. Marin County is situated in Sunset Zones 15, 16, and 17. These zones give a general idea of the climate conditions in your neighborhood. They also help to guide your plant selection and planting times. Here are the cities and towns in Marin County and their associated Sunset climate zones.
Marin gardeners can also use the USDA Plant Hardiness Zones to help choose appropriate plants.
• Hardiness zones reflect average annual low temperatures.
• Gardeners and growers across the country use these standards to determine whether plants are likely to withstand cold temperatures.
• Many plant tags and online plant descriptions include the hardiness zone.
• The Plant Hardiness Zone Map is published by the U.S. Department of Agriculture. You can look up your zone on this map. Marin’s hardiness zones are:
10a (minimum annual winter temperatures of 30 to 35 degrees Fahrenheit), and
9b (minimum temperatures 25 to 30 degrees Fahrenheit).
To be sure a plant will survive in your garden, make sure the label describes the plant as hardy to Zone 9b/10a. Plants with lower hardiness zone ratings will also endure our winters. However, some plants, such as peony and many lilacs, prefer colder winters than our gentle climate can provide.