Over 1,500 years ago a Greek physician, pharmacologist, and botanist by the name of Pedanius Dioscorides wrote a five-volume work titled De materia medic. Literally interpreted, the title means "On Medical Material," and for well over a millennium it was regarded as the most influential work on plant pharmacology. The work is our primary source of evidence of the medicines used by the Greeks, Romans, and other cultures of antiquity. It also gave early identities to plants well before the time of Linnaeus, father of the binomial system of nomenclature.
The early work of Dioscorides ultimately gave rise to what became known as the "Doctrine of Signatures." Developed more fully by Paracelsus in the 16th century, this philosophy suggests that "Nature marks each growth ... according to its curative benefit." In other words, plants bearing parts (having signatures) that resembled human body-parts were thought to have useful relevance to those parts. For example, Euphrasia, or eyebright, is a genus of plants with small, nodding flowers said to resemble the human eye. Thus, in the 16th century, Euphrasia was thought to be helpful in treating eye infections.
Apparently, someone in antiquity thought the leaves of a certain member of the Boraginaceae (forget-me-not) family of plants looked very much like diseased human lungs. Thus, lungwort got its rather unappealing common name. In 1753, Linnaeas obliged by giving the plant the scientific name of Pulmonaria officinalis. Pulmonaria is derived from Latin pulmo, meaning lung. The specific epithet, officinalis, is derived from the Medieval Latin officīna which was the storeroom of a monastery, where medicines and other necessaries were kept. As a specific epithet, officinalis normally is reserved to describe plants with medicinal, herbal, or culinary uses.
Today, we recognize there is no association between the appearance of a plant and its potential medicinal value. However, plants continue to be used in a therapeutic manner. Even in the 21st century, the World Health Organization speculates that more than two billion people worldwide likely are heavily dependent on medicinal plants for their health care.
The value of lungwort as a medicinal plant has yet to be scientifically substantiated. Its value as an ornamental is beyond question. In the garden, lungwort is an attractive perennial that blooms early in the year and continues to lend aesthetic appeal throughout the growing season because of its unusual foliage.
Native to Europe and western Asia, there are about 18 species of Pulmonaria found growing in the wild. Most are herbaceous perennials that form clumps or rosettes as they grow. The below-ground parts of lungwort plants consist of slow-growing rhizomes that produce adventitious roots. Hardy to USDA zone 3, lungworts spread very slowly via their rhizomes. However, they are not considered invasive.
Lungworts are grown for their attractive foliage and flowers. The leaves of most species and cultivars are spotted with silver or white. However, some of the newer varieties have silver or white leaves with green spots or margins. In all cases they are basal in growth habit, three to five inches in length, ovate or elliptic in shape, and quite hairy.
The flowers of lungwort are funnel-shaped, about ¾ of an inch long in mid-spring. They are borne on flowering stems that rise above the plant's foliage. The color of lungwort flowers changes with age. In most cases they are pink when they open but change to rose-violet. At maturity they deepen to a blue color. It is quite common to have different colored flowers on one plant at the same time which adds to their novelty.
The lungworts are relatively easy to grow if provided with suitable environmental conditions. They prefer cool temperatures and an exposure of part to full shade. Soil should be high in organic matter and well drained. Although plants should never be allowed to dry out, they are equally intolerant of soggy, wet conditions. Lungworts struggle in hot, dry locations which results in leaf scorch. Therefore, avoid planting them in full sun.
Lungworts 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 normally is sufficient. Additionally, lungworts do not have many serious pest problems. Powder mildew can infect plants where air circulation is poor. Slugs, commonly found in shady, moist areas, can damage foliage as they feed.
Today, a majority of the noteworthy lungwort cultivars are inter-specific hybrids of Pulmonaria saccharata, P. angustifolia, and P. longifolia. The following is a list of cultivars that should perform well in our area.
- 'Berries and Cream' produces silver foliage and rosy-pink flowers.
- 'Bertram Anderson' has long, narrow, dark green leaves with silver spots. It bears flower that are violet blue.
- 'Excalibur' bears silvery white foliage with green margins and midribs. Its flowers are pink.
- 'Mrs. Moon' is an old favorite with silver-white spotted leaves. It bears pink buds that mature into light blue flowers.
- 'Pierre's Pure Pink' has green leaves dotted with silvery spots. It produces pale pink flowers in spring.
- 'Raspberry Frost' is new to the plant world. It bears coral-red flowers which contrast beautifully against a backdrop of silver-blotched foliage edged in creamy white.
- 'Raspberry Splash' is a very attractive variety that produces green foliage mottled with silver spots. A very floriferous variety, it bears raspberry-pink flowers.
- 'Roy Davidson' has dark green leaves with silver-white spots. Its flowers are pale blue.
- 'Sissinghurst White' is grown for its silver-white spotted foliage and white flowers.
- 'Smokey Blue' produces silvery spotted foliage. Its pink flowers turn blue with age.
- 'Spot On' has green leaves with silver speckling. Its salmon pink buds transition to rich blue flowers at maturity.
- 'White Wings' produces white flowers that are larger than 'Sissinghurst White.' Foliage has silver spots.
In all cases lungworts are excellent companions for other shade-loving plants. They can be used as specimen plants in shady beds and borders, or as a groundcover for a shady site. Attractive to birds and pollinators, they are considered to be deer resistant.