For color in your garden and flower beds during the winter season and the early spring, plant cold tolerant hardy annuals such as pansies, foxglove, larkspur, ornamental kale, cornflower, sweet alyssum, stocks, dianthus and calendula. These hardy annuals can survive light frost and some freezing temperatures, but typically decline as the temperatures grow warmer. Hardy annuals thrive in areas of full sun to light shade. Plant hardy annuals in the fall or before the last frost date in the spring.
Half-hardy annuals are damaged by frost but tolerate periods of cold weather. Baby's breath, blue sage, cleome, forget-me-nots, snow-on-the-mountain, starflower, candytuft, love-in-a-mist and torenia are considered half-hardy annuals. Plant half-hardy annual seeds or plants after the last spring frost; the seeds do not require warm soil temperatures to germinate. Half-hardy annuals bloom in the late spring and early summer before declining during hot summer temperatures. Some half-hardy annuals bloom again when temperatures cool in the late summer and fall.
Plant your flower bed with a combination of cool-season and warm-season annuals for color from the late spring throughout the summer and into the fall. Cool-season annuals have the best flower production when the daytime temperatures hover between 70 and 80 degrees, often in the late spring and early fall. Cool-season annuals include petunias, poppies, creeping zinnia, cupflower, phlox, lobelia, snapdragons and geraniums.
Include an assortment of warm-season annuals in your flower garden to enjoy flowers during the heat of the summer. Warm-season annuals produce the most flowers when daytime temperatures are in the 80s and 90s, effectively filling in with flowers when the cool-season annuals begin to fade. Warm-season annuals include sunflowers, four-o'clocks, pentas, impatiens, zinnias, moss rose and periwinkle.
If your flower bed sees more shade than sun, plant annual flowers to brighten your landscape. Impatiens, wax begonia, rose balsam, silver bells, wishbone flower, silver bells, fuchsia, bells of Ireland, perilla and elephant ear prefer to grow in areas of shade to partial sun. Some shade-loving flowers that grow from bulbs are treated like annuals, such as tuberous begonia and caladium. These plants produce flowers throughout the season, but should be removed from the ground and stored during the winter.