Zones temperature and hardiness:
USDA zones are based on 30 year temperature records kept at official weather reporting stations. Of course the weather can vary widely between those reporting stations so it is important to pay attention to weather in your own garden. Most importantly it is best to know that our climate is similar to others but when it comes right down to it , it is our own. Therefore, we don’t like to classify it as anything other than what it is. If you live in western Washington, its western Washington’s climate. In western Oregon, guess what? You got it.
We have a winter wet, summer dry climate. Winters are cool and wet, the amount of time we spend between 35º and 55ºF- IT CAN BE MONTHS! Spring, quite often is showery and cool and summer is dry and pleasant, intermittently hot, before fall which is quite often showery and wet. Arctic air can intrude and last for a day or up to 10 days. It is usually gone pretty quickly and gives us our coldest weather in quick dramatic shots. Cold hardiness, the adaptation of plants to take cold has many determining factors. It is important to meet a plants ultimate cultural requirements for it to achieve its full hardiness to cold. Even when those requirements are met- topsy turvy weather can cause even more havoc. Take into account a plants adaptation to soils, moisture, siting and we think its best to look at each plant on a case by case basis.
In western Oregon and Washington our winters fall into these zones.
