I recommended two books on the Winter Blues podcast so I have listed the links to those two books below so you can find out more about them. Happy reading!
#1 - Wonders of the Winter Landscape by Vincent Simeone
Although North America suffers through several dreary months of winter each year, this guide describes trees and shrubs that make the barren winter landscape a wonderland of texture and color.
#2 - Winter Blooming Shrubs by Michael Buffin