Wednesday, 4 May 2011

Pacific NorthWest and the Zone Challenge

The  Pacific Northwest is an area of North America roughly covering Southwest B.C., Washington, and Oregon, west of the mountains. In the gardening world, our climate is unique, and considered a modified Mediterranean climate with wet Winters and dry Summers. In fact, 80% of our precipitation falls between October and April.Our Winters are mild with occasional cold snaps, and our Springs are long, cool and moist. Our Summers are warm and dry, with cool evenings and our Autumns are warm and dry until late October, when the rainy season starts.

So what does all this mean to the gardener? Mild Winters mean insects overwinter readily and the rain encourages fungal diseases, moss and algae. Cooler Summers mean late-ripening of tomatoes and limited success of other heat loving plants. Plants that would normally be considered hardy in our zones (6-9) don't always succeed. Our lack of hot summers to ripen new growth on shrubs can result in Winter die-back, and our mild Winters trick plants into thinking Spring is here, when indeed it is not.  Zone 7 in the Pacific Northwest is nothing like zone 7 in the Eastern United States, and our zone 9 nothing like Texas or Florida. Zones indicate nothing about humidity, summertime heat, or even how long the growing season is.

Plants described as "difficult" are sometimes the very ones that do best in our area, while "easy" ones do poorly. I have experienced this myself with many annuals.   The best advice I can give when it comes to choosing new plants for your garden is to buy from local nurseries, which tend to offer plants that do well in the area you live. I have found my local library to have a good selection of gardening books, many focused on the Pacific Northwest. Comments always welcome and appreciated. Happy Gardening!
Tulip Purple Flag

Interesting new growth on Platycodon (Balloon Flower)


  1. The most successful (some too successful!) plants in my garden have come from friends, plant swaps, and local plant sales.

    Thanks for the perspective, I now understand a bit more why I don't trust those "zone" categorizations.


I just love reading your comments and appreciate the time it takes you to write them. In the past I have had word verification turned off but due to the amount of spam comments, I have now turned it on. I hope it won't keep you from posting.