I live in Seattle. Winters are gray and dark, but not particularly cold. I find a light box helpful for the SAD. I also take fish oil (I should have gills), vitamin D, and antidepressants. Like most gardeners, I read garden books all year, but especially in the winter. I have orchids and other house plants in every window. I have planted my garden with winter color in mind. It is possible to have flowers here, but also red, gold, and orange bark and berries. And I PLAN, and DREAM, and VISUALIZE gardens in my head. Many a garden has been planned , grown, and dismantled by winter’s end.