Answer: The USDA zone map is relatively general and doesn't take into consideration elevations or bodies of water which have a definite influence on gardening zones. A better source to help you pinpoint your gardening zone is Sunset Western Garden Book. The book places you in their zone 5, with an average minimum winter temperature of 28F. Try locating a copy of the book at your local library (ISBN# 0-376-03851-9. Another local source of information is the website http://gardening.wsu.edu which features 'Gardening in Western Washington'. Good luck with your garden!
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