Although it may seem that sun-loving flowers steal the show with their vibrant colors, there are annuals that thrive and add interest to shaded gardens. However, it is important to define what is meant by "shade." Most annuals for shade gardens do well in partial shade, needing three to four hours of morning sun to produce healthy blooms. These shade lovers all require soil that is loose, rich with humus and organic matter, and must be kept evenly moist but not soggy or water-logged. If you provide your plants with these basic requirements, your efforts will be rewarded with lovely flowers that brighten and provide color to the shade garden.
Impatiens (Impatiens walleriana)
These colorful plants bloom profusely in shades of pink, rose, red, lavender, white and orange. Bicolor varieties are also available. Impatiens bloom all summer long with no dead-heading required. The flowers are either single, flat blooms or double blooms resembling roses. Ranging in height from 6 to 10 inches, impatiens are a colorful and versatile choice for shady areas. Plant them as a cheerful ground cover, in the shaded border to provide color among ferns and hostas, as an edging at the front of a flower bed or in containers. Impatiens attract hummingbirds and butterflies.
Lobelia (Lobelia erinus)
Lobelia plants produce mass quantities of delicate flowers in shades of blue, violet, pink, red and white. The flowers bloom from early summer to frost. The bushy varieties are well suited for borders and edgings, and are good companion plants for hostas and impatiens. The trailing cultivars make lovely additions to hanging baskets and window boxes. Lobelia flowers attract butterflies.
Forget-Me-Nots (Myosotis sylvatica)
These early-bloomers produce small, deep blue flowers on plants that grow from 6 to 12 inches tall. Forget-me-nots bloom from early spring to midsummer and combine well with spring bulbs. The delicate blooms help camouflage the bulbs dying foliage. Forget-me-nots are especially attractive in the informal flower garden as they are a good cutting flower. Cut the plants back after flowering to prevent them from self-sowing.
Wax begonias (B. semperflorens) have an upright growth habit with heights ranging from 8 to 15 inches. Flowers, either single or double, bloom continuously from spring to frost in shades of red, pink, white and bicolors. The leaves add interest as well, available in various shades of green and bronze. Wax begonias are good plants for containers, edgings or summer color in a shade garden.
Tuberous begonias (B. tuberhybridacultorum) have larger, showier blooms than wax begonias and are also somewhat more demanding. They do best when night temperatures consistently fall below 65 degrees F. Tuberous begonias bloom from summer to fall in a wide range of colors except blue. These plants are especially well-suited to growing in containers, either alone or with other shade plants such as impatiens and lobelias.