Foliage instead of flowers
A recent photo of a winter's garden here in the San Francisco Bay Area, showing that foliage can be every bit as interesting as flowers for garden interest. In fact, this garden keeps the colorful foliage year round. I actually prefer using foliage color primarily, in this case mostly succulents. A monochromatic color theme of blues, silvers and grays contrasting with different shades of green are the dominant colors.
Here is a link that might be useful: Foliage over flowers