Flower planting in Oregon
When is the best time to plant flowers?
Tillamook County Oregon
This is definitely a good time to be planting bulbs, e.g., daffodils, narcissus. It is also a good time for tree and shrub planting. You should, however, wait to put most flower plants in the ground until late March/April when the chance of a late frost should be diminished. It really depends on the microclimate(s) in your yard. If you don't get a lot of frost, you might try planting pansies, violas, hellebores, English primroses, geraniums for some winter color.
Here is an article from Oregon State Extension with some advice on coastal gardening from Master Gardener Carla Albright who lives in Tillamook County.
You can also check out Oregon State Extension Monthly Garden Calendars for good advice on garden planning and planting. https://extension.oregonstate.edu/collection/monthly-garden-calendars