By Richard Jauron
Iowa State University Extension
When selecting perennials for shady areas, hostas are the first choice of many gardeners. Another excellent choice for the shade garden is the lungwort (Pulmonaria spp.).
Lungworts are grown for their attractive foliage and flowers. The leaves of most species and varieties are hairy, ovate to elliptic in shape and spotted with silver or white. However, some of the newer varieties have silver or white leaves with green spots or margins. Lungworts also produce clusters of funnel-shaped flowers in early spring.Flowers may be red, violet, blue, pink or white.
Pulmonarias are low-growing, clump-forming, rhizomatous perennials. Most species and varieties grow nine to 18 inches tall. Plants may eventually spread two to three feet wide. Lungworts can be used as specimen plants in perennial beds and borders or as a groundcover.
The rather odd common name refers to the belief in the 16thand 17th centuries that the plant was an effective remedy for lung diseases. (Pulmonaria is derived from the Latin pulmo, the lung.) Other common names include Bethlehem sage, Jerusalem cowslip, spotted dog and soldiers and sailors. Lungworts are easy to grow, low maintenance, long-lived perennials.
Lungworts grow best in partial shade. Pulmonarias also prefer moist, well-drained soils that are high in organic matter. Soils with low levels of organic matter can be improved by incorporating compost, peat moss or well-rotted manure into the soil prior to planting.
Lungworts do not perform well in dry or wet sites. Plants will wilt badly in dry areas. They often die in wet soils.
Lungworts like an even supply of moisture during the growing season. For best performance, water lungworts every 7 to 10 days during prolonged dry periods. When watering, soak the soil to a depth of 10 to 12 inches.
Pulmonarias don’t require frequent or heavy fertilizer applications. Sprinkling a small amount of an all-purpose garden fertilizer, such as 10-10-10, around each plant in early spring is sufficient.
Lungworts don’t have serious pest problems. Powdery mildew can be a problem in areas with poor air circulation. Slugs also can damage the foliage.
Though they can be left undisturbed for years, lungworts can be propagated by dividing the clumps in late summer/early fall or after flowering in spring. Carefully dig up the entire clump and divide the clump into sections with a sharp knife. Each section should contain several leaves and a portion of the root system. Replant immediately.
Here is a list of some of the most noteworthy lungwort varieties. Most of the following are hybrids of Pulmonariasaccharata, P. angustifolia, and P. longifolia.
‘Berries and Cream’ has silver foliage and rosy pink flowers.
‘Bertram Anderson’ has long, narrow, dark green leaves with silver spots. Flowers are violet-blue.
‘British Sterling’ produces silvery leaves with narrow, green margins. Magenta flower buds mature to blue flowers.
‘David Ward’ has dull green foliage with thin, white margins. Coral flowers in spring.
‘Excalibur’ bears silvery white foliage with green margins and midribs. Pink flowers.
‘Janet Fisk’ has heavily marbled foliage and pink flowers which fade to blue.
‘Mrs. Moon’ is an old favorite with silver-white spots. Pink buds mature to light blue flowers.
‘Pierre’s Pure Pink’has green leaves dotted with silvery spots. Pale pink flowers in spring.
‘Raspberry Splash’ produces green foliage mottled with silver spots and raspberry pink flowers.
‘Roy Davidson’ has dark green leaves with silver-white spots. Flowers are pale blue.
‘Sissinghurst White’ is grown for its silver-white spotted foliage and white flowers.
‘Smokey Blue' produces silvery spotted foliage. Pink flowers turn to blue.
‘Spilled Milk’ has wide, silvery foliage accented with a few green spots. Magenta flowers fade to pink.
‘White Wings’ produces white flowers that are larger than ‘Sissinghurst White.’ Foliage has silver spots.
When selecting perennials for the shade garden, don’t let the rather odd common name deter you. Lungworts are great additions to shady landscape sites.
Richard Jauron, Horticulture, (515) 294-1871, firstname.lastname@example.org
Jean McGuire, Extension Communications and External Relations, (515) 294-7033, email@example.com