One of the most visually interesting plants in my garden is lungwort, Pulmonaria officinalis, in the borage family, Boraginaceae; the flowers are both red and blue and the dark green leaves have white spots, making it an easy plant to recognize. It is low-growing and has spread as a pretty ground cover. Lungwort is native to Europe and widely distributed there, liking shade and cool temperatures. It can be grown in USDA Zones 3-9 (depending on the variety) and has naturalized in New York, Vermont, Ontario, Quebec, and Nova Scotia.
The name lungwort and the Latin name Pulmonaria both refer to its traditional use as a treatment for respiratory problems. (Wort is an old word meaning “plant.”). Before it was called lungwort, Europeans called it by a variety of names including Jerusalem sage, Jerusalem cowslip, Virgin Mary’s tears, Virgin Mary’s milk, Joseph-and-Mary, Soldiers-and-Sailors and more. (Dage of Jerusalem is a typo for sage of Jerusalem. A medical publication, probably PDR for Herbal Medicine, made that error and you can find it repeated on medicinal herb web sites.)
The spots on the leaves, a very distinctive characteristic, gave rise to the names Virgin Mary’s Milk, seeing the spots as milk droplets, and Virgin Mary’s Tears, with the spots as teardrops. Her eyes, they said, were blue as the fully-opened flowers and her eyelids red from weeping, like the younger flowers. It was bad luck to weed out this plant of the Virgin.
Other common names, Joseph-and-Mary, Soldiers-and-Sailors, alluded to the two colors of the flowers.
There are other, very different plants called lungwort, in particular the lichen Lobaria pulmonaria (not actually a plant, but rather an alga growing inside a fungus), and also the flowering plants Helleborus niger, black hellebore, the Christmas rose, and the composite Hieracium murorum, wall hawkweed.
The name lungwort for Pulmonaria officinalis came late and is based on the spotted leaves looking like (diseased) lungs. In the Christian medical teachings of Medieval and early modern Europe, God put all things on earth for human use and, so that humans would know how to use them, made them they look like their intended use. This was the Doctrine of Signatures. Lungwort was one of the easiest examples; the leaves look like lungs, so they treat lung problems. Today you can read both that lungwort does nothing for the lungs and that it will bring relief. Usually the leaves are dried and made into a tea. They are mucilaginous and contain tannins, so the drink is soothing. The leaves contain modest amounts of compounds such as antioxidants and may have therapeutic value but no one lists any actual studies of efficacy.
Botanically, the white spots are created by air pockets in the leaves; the strong green of the leaf is obscured there. The air in the air pockets helps keep the plant cool on warm days.
You can eat lungwort. The leaves can be cooked like spinach or added to a salad. They are hairy, which is not common in our foods, but with other leaves in the salad, makes a nice contrast. Cooking destroys the hairs.
And it is a pretty plant. The flowers start of pink or red and as they open, turn purple and then blue, producing a wonderful splash of color. Flower color changes because as the flower ages, the pH in the petals shifts, changing the color. It appears that this gives lungworts an advantage for pollination. The mass of red to blue flowers attracts the attention of bees (most of the pollinators are bees, some flies, and rarely a butterfly) from a distance. The bigger the mass of color, the farther away you can see it, of course. When the bees get close, they quickly learn that the red flowers are younger and have much more nectar and pollen. Consequently the bees don’t search through a bunch of nectarless, already-pollinated flowers and are quickly rewarded. And, knowing red means the best flowers, bees will move between plants to red flowers, which facilitates cross pollination for the plant.
There are fifteen species of Pulmonaria, native various places across Eurasia, several of which have been cultivated for a long time. In a garden, lungworts cross freely between species, so there are many hybrids available, varying dramatically in leaf and flower color. To consume it, Pulmonaria officinalis is preferred. Otherwise, enjoy the varieties.
Eland, S. C. 2013. Plant Biographies. CD. Also online.
Gruenwald, J., T. Brendler, and C. Jaenicke, editors. 2007. Lungwort. PDR (Physicians Desk Reference) for Herbal Medicine. 4th edition. Thomson Healthcare Inc., Montvale, New Jersey.
Lungwort Health Benefits. HealthBenefitstimes.com Accessed 1/8/20
Missouri Plant Finder. Pulmonaria. (several varieties). https://www.missouribotanicalgarden.org/PlantFinder. Accessed 12/28/19.
Oberrath, R. and K. Böhning-Gaese. Floral color change and the attraction of insect pollinators in lungwort (Pulmonaria collina). Oecologia. 121: 383-391. 1999.
Plants for a Future. Pulmonaria officinalis, L. pfaf.org Accessed 1/3/20
Vickery, R. 1995. Oxford Dictionary of Plant Lore. Oxford University Press, Oxford, England.WFO (World Flora Online). 2020. Pulmonaria L. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000032171. Accessed on: 07 Jan 2020.
As a former Professor of Biological Sciences at the University of Nebraska-Lincoln, Kathy Keeler’s specialties range from ant-plant interactions to grass genetics to studies of prairie plants.
Retired, she now pursues travel and history, endlessly fascinated by different places and times.
And, wherever Kathy goes, she is irresistibly drawn to plants.
On this website and on her blog you can gain a deeper enjoyment of the natural world and discover information about plants that will delight and enchant you.