You can give any room a fresh seasonal decor by making small changes.
Alternate two sets of decorative pillow covers — one set for spring/summer and the other for fall/winter.
Purchase reversible drapery panels so they can easily be turned with the changing of the seasons. Pale tone(s) on one side for spring/summer with deeper tone(s) on the reverse for fall/winter.
When displaying art, change it seasonally. Light and bright for warmer seasons, richer and warmer for when the weather turns cool.
Switch a light throw with a cozier one for cooler seasons.
Use light and bright themed flower arrangements for spring/summer. Replace with fall colored pieces accented with fall leaves and fruit in fall/winter.
Warm months use a cool cotton matelasse bed cover, switch to a thick down comforter for cold months.
