You at an advantage to enjoy winter flowering bedding plants if your winter temperatures never drop much below 20 degrees Fahrenheit. The plants' blooming and overall performance is best when soils remain moist and sunshine plentiful and daytime temperatures range from 45 to 70 degrees Fahrenheit. Northern areas of the United States remain too cold and snowy to enjoy these plants in winter. Contact a local plant nursery and inquire about bedding plants available, if any, for use in winter in your climate.
Violas (Viola spp.)
Violas include the closely related pansies and Johnny-jump ups. The main difference between the two is the number and size of flowers, with pansies producing much larger blooms. These annuals are usually planted in autumn and allowed to grow slowly and flower over winter, especially in U.S. Department of Agriculture hardiness zones 7 through 9. Plants may look rough when temps drop below 20 degrees Fahrenheit, but will bounce back when warmth returns.
Wallflowers (Erysimum spp.)
Wallflowers tend to grow their best in nonacidic soils in sunny locations. A close relative of mustard, wallflowers grow quickly and appreciate cool winter temperatures that don't linger too long below 25 degrees Fahrenheit. Many varieties exist today, some growing tall and upright, others into short tufted clumps. Their many stems are topped in clusters of yellow, orange, salmon, mauve or pink blossoms.
Snapdragons (Antirrhinum spp.)
Cool, relatively frost-free winter regions can enjoy the repeated flowering of snapdragons from fall to mid-spring. Tall and compact selections exist, all producing upright spikes of flowers that release a faint sweet fragrance in the early evening. Cut off spent flower spikes to encourage re-flowering.
Pinks (Dianthus spp.)
The vast majority of pinks are perennials, but since they grow quickly and appreciate cool temperatures, many are grown as annuals and then pulled up once the plant vigor or blossoming wanes. Best in nonacidic soils in full sun, pinks will provide winter bedding color across USDA zones 8, 9 and 10 in winter.
Pot Marigolds (Calendula spp.)
Consider planting pot marigolds from seed in autumn so that they are of flowering size come winter in USDA Zones 7 through 9. Don't confuse these orange and yellow flowers with the summer marigold (Tagetes spp.) that has feathery foliage. Pot marigolds do best with temperatures ranging from 25 to 70 degrees Fahrenheit. Remove dead flowers to encourage new blooms to form.