The combination of acidic soil in a shady spot creates the need for a special type of plant. Fortunately, there are many choices that produce colorful blooms in that growing condition. While azaleas, heaths, evergreens, laurels and camellias are popular choices, others also exist. Some choices worth considering are foxglove, parrot lily, vase plant, twinflower and caladium.
In addition, you should test the pH of the soil every three years because acidity levels can change as a result of fertilizers, soil amendments, and acidic or alkaline water.
Foxglove, or Digitalis purpurea, is one of about 20 Digitalis species from the Scrophulariaceae, or figwort, family. Its tubular flowers grow on stalks that reach 3 to 5 feet tall. It requires moist soil. Propagate via seed in late summer or fall. All of the foxglove plant is poisonous, repelling even deer and rabbits.
Parrot lily, or Alstroemeria psittacina, is a member of the Amaryllidaceae, or amaryllis, family and attracts birds to the garden. Red flower clusters on 8- to 12-inch stalks bloom in summer. It requires rich soil and prefers moist airy (sand, not clay) soil, but it can tolerate moisture extremes. It is an invasive perennial that is propagated by seed.
Vase plant, or Aechmea distichantha, is an evergreen perennial from the Bromeliaceae, or pineapple, family. Its green leaves sport brown spines that arch in the leaf. The leaves are an inch wide and up to 3 feet tall, creating a funnel-shape appearance. The flowers are blue, white or purple.
Twinflower, or Mitchella repens, is from the Rubiaceae, or madder, family. The evergreen vine features small (less than an inch) dark green leaves and fragrant flowers. The vine reaches only 2 inches tall but can spread 12 inches. Funnel-like pink or white flowers bloom in the summer.
Caladium, or Caladium bicolor, is from the Araceae, or Arum, family. The perennial with large leaves that vary in shape, size, and color averages 2 feet tall by 2 feet wide. There are over 1,000 named varieties of caladium. The plants need rich soil and a lot of water; they do badly in dry climates. To propagate, divide the tubers.