Nearly all annuals require at least 6 hours of sunlight to blossom. Most will tolerate afternoon shade if planted in areas with morning sun. Even if an annual thrives in shade, it still needs a few hours of sunlight. Annuals that tolerate shade are used for color and to brighten up shady flower beds. Avoid planting your flowers in standing water. Always wait to plant your annual flowers until the soil temperature warms up.
Annual candytuft (Iberis umbellate) forms 8- to 10-inch-wide mounds of narrow leaves. The flowers cluster together on stems that are 8 to 12 inches tall from late spring through the middle of summer. Candytuft blossoms are white, pink, purple, rose and red.
Flowering tobacco (Nicotiana alata) produces rosettes of oval to pointed green leaves reaching 12 inches wide. Flower stalks loom over the leaves at the height of 18 to 36 inches tall with trumpet-shaped flowers. Flowering tobacco blossoms show up in white, pink, purple and red colors. Only the white variety of flowering tobacco is fragrant.
Forget-me-nots (Myosotis sylvatica) bloom in masses of sky blue blossoms on 12 to 18 inch stems. The flowers mix in with clumps of narrow, lance-shaped leaves. Forget-me-nots enjoy partial shade and go well with spring blooming bulbs.
Impatiens (Impatiens wallerana) are a colorful annual groundcover that grows 6 to 24 inches tall. The neat, shrubby mounds are created by succulent stems and lance-shaped, green leaves with scalloped edges. The flowers appear in late spring until autumn frost in white, pink, red, orange and lavender shades. Impatiens are the champion growers in shade gardens.
Monkey flowers (Mimulus x hybridus) are a summer blooming annual that reaches 12 to 24 inches in height. This annual flower blooms in yellow, cream, orange and red colors in 6 inch wide clusters. Mulch around the monkey flowers to keep the soil cool during hot summer weather.
Pansies (Viola x wittrockiana) grow 6 to 8 inches tall with wide blossoms that reach 2 to 5 inches wide. Flower colors include white, pink, red, orange, yellow, purple, blue and almost black with yellow centers. Clumps of narrow, green leaves spread 8 to 12 inches wide. Mulch around the pansies to keep the soil cool and moist during the summer.
Wishbone flowers (Torenia fournieri) are shady-loving annuals with shy purplish-blue flowers with yellow throats. Each flower has two curved stamen that look like a wishbone. The pointed leaves clump together and develop a reddish-purple tint. Wishbone flowers also come in white and pink shades.