When selecting plants for the shade garden, one group of plants that is often overlooked are native woodland wildflowers. Since they are native to the state, woodland wildflowers are completely hardy. They also perform well when given a good site. Many are very attractive. When browsing through garden catalogs this winter, consider some of the following woodland wildflowers.
The wild columbine (Aquilegia canadensis) is found throughout the state. It commonly grows on moist, rocky slopes. The wild columbine produces 1- to 2-inch-long, scarlet and yellow flowers. The flowers hang downward on long individual flower stalks. Plants bloom from April to July. Wild columbines grow approximately 2 feet tall. The wild columbine is suitable for natural woodland areas and perennial borders. It performs well in full sun to partial shade. The native columbine is a relatively short-lived perennial, but it self-sows freely once established. Young plants are easy to transplant. Large, mature plants, however, are difficult to move because of their deep root system.
The distinctive foliage and flower of Jack-in-the-pulpit (Arisaema triphyllum) is an attractive plant in the woods and in the garden. Each plant consists of one or two 3-lobed leaves which are borne on 12-inch-long petioles. The flower gives the plant its common name. Each flower consists of a club-like spadix ("Jack" or the preacher) and the leaf-like spathe (pulpit) which curves up and over the spadix. The spathe may be green, purple-brown, or striped. The flower is followed by a cluster of berries which turns bright red in the fall.
Jack-in-the-pulpit is commonly found in moist woodland sites in Iowa. It is relatively easy to grow in the home garden. Its basic requirements are partial shade and moist soils.
Goat's beard (Aruncus dioicus) is a large native plant that is often grown as an ornamental. Native populations are limited to several Iowa counties bordering the Mississippi River. Native plants in these counties are typically found in rocky, wooded slopes.
Goat's beard is not a plant for small gardens. Plants may grow 4 to 6 feet tall and 6 feet wide. Its pinnately compound leaves are 2 to 3 feet long. Dense spikes of creamy white flowers are produced in early summer.
Because of its large size, goat's beard is best used as a background plant or in the center of large beds. It prefers moist soils and partial shade.
Wild ginger (Asarum canadense) is found throughout the state. It is commonly found on moist, wooded slopes. Wild ginger often forms large colonies on the forest floor. Each plant usually consists of 2 kidney- or heart-shaped leaves. A single flower is borne close to the ground and is often covered by plant debris on the soil surface. The flower is bell-shaped and maroon to brown in color. Plants bloom in April or May.
The common name, wild ginger, refers to the spicy, ginger-like aroma produced when the leaves or rhizomes are crushed. In fact, early settlers used the rhizomes as a substitute for true ginger (Zingiber officinale).
Wild ginger prefers moist soils that contain large amounts of organic matter. Sites in partial to deep shade are best. Use wild ginger as a groundcover or edging plant.
A close relative of the old-fashioned bleeding heart (Dicentra spectabilis) is Dutchman's breeches (Dicentra cucullaria). Dutchman's breeches are found throughout the state in moist woodlands. It blooms in April and May. The common name, Dutchman's breeches, comes from the flower's resemblance to a pair of Dutch pantaloons. Four to ten white, pant-shaped flowers hang upside down from an arching flower stalk. At the "beltline" of the pant-shaped flower is a small area of yellow. The gray-green to blue-green, fern-like foliage disappears by mid-summer.
Dutchman's breeches grows best in moist, woodland soils. It is best planted in patches in natural areas.
Virginia bluebells (Mertensia virginica) is native to moist woodlands. Flowers are borne in nodding clusters. Pink buds open into trumpet-shaped, light blue flowers. The plants, approximately 1 to 2 feet tall, quickly die back to the ground after blooming. Because of their ephemeral nature, Virginia bluebells are often planted between slower growing perennials or in small groups in the perennial border. They are excellent for natural areas.
Woodland phlox (Phlox divaricata) is found throughout the state. It often grows in large patches in moist woods. Plants are approximately 12 to 18 inches tall. Flowers are blue to lavender, occasionally white. Plants bloom in April and May. Woodland phlox performs best in moist soils and partial shade. Plants can be placed in the front of the border or tucked between other shade tolerant perennials. They can also be planted in drifts in woodland areas. Several varieties are available. 'Fuller's White' has creamy-white flowers, while Phlox divaricata var laphamii has deep blue flowers.
The graceful, arching stem of the Solomon's seal (Polygonatum biflorum) is common in woodland areas throughout Iowa. Each plant produces only one stem per year. The long, unbranched stem may be up to 6 feet long. Solomon's seal bears yellowish-green to greenish white flowers in May and June. The flowers hang down in clusters from the leaf axils. The flowers are followed by pea-size berries which turn blue-black in late summer. Solomon's seal produces a thick, horizontal, much-jointed rhizome underground. When the stem dies back in the fall, it leaves a large circular scar on the rhizome. Since only 1 stem is produced each year, the age of the plant can be determined by counting the number of scars on the rhizome.
Solomon's seal prefers shade and cool, moist soils. Plant several rhizomes (5 or more) in an area for a full appearance.
Bloodroot (Sanguinaria canadensis) is a member of the poppy family. Plants bloom in March and April. As the plant emerges in the spring, a leaf is tightly coiled around the flower stalk. The single, white flower contains 8 to 16 petals. After the flower opens, the large, deeply lobed leaf unfurls. Below ground the plant produces thick, tuber-like roots. The common name, bloodroot, refers to the bright red juice which oozes from the root when cut or broken. Native Americans used the red juice to dye clothing. They also used the red juice to decorate their faces and bodies for ceremonial occasions.
Plant bloodroot in small clumps or colonies in natural areas or as edging plants in perennial borders. Other possibilities include May apple (Podophyllum peltatum), shooting star (Dodecatheon meadia), false Solomon's seal (Smilacina racemosa), merrybells (Uvularia grandiflora), and others.
This article originally appeared in the March 1, 1996 issue, p. xx.