Plant spotlight
Pulmonaria ‘Silver Bouquet’
Pulmonaria, or lungworts as they are commonly called, are bold-textured clumping woodland perennials, prized for their unique silver-spotted deer-resistant foliage. Pulmonarias, which have long been favorites of temperate climate shade gardeners, flower in late winter/very early spring, usually beginning around the end of February with the hellebores.
Lungwort flowers, most of which emerge usually either pink or violet, typically change to cobalt blue as they age. The flowers are borne in corymbs on short stalks that top out just above the foliage. Pulmonaria clumps top out at 6-10” tall with a 2’ widespread and generally retain their foliage until late winter, becoming mostly deciduous just before the new season’s flowering and regrowth begin.
As is the case with many plants that have been cultivated over a long time, their names were often derived from medicinal uses. Pulmonaria, the root of pulmonary, refers to lungs, as does the common name, lungwort. Pulmonaria has indeed been used to treat chest ailments since the early 1500s.
Many of the early pulmonaria introductions in our region failed to thrive in the heat and humidity of the southeast US. The genus Pulmonaria is comprised of sixteen species that can be found from cold alpine forests to warm climates from Europe and into Central Asia. Since much of the early breeding and selection was done in Central Europe, little attention was paid to selections for hot, humid climates. Finally, in the 1970s breeders began using the Southern European native Pulmonaria longifolia, which imparted heat adaptability to the lungworts, and their popularity soon began to soar in warmer climates.
Until the early 1980s, all commercially available lungworts had green leaves with random silver spots. Plant breeders now wanted to see how many spots a leaf could have, and if there were a possibility of an all silver leaf. The silver spots on Pulmonaria leaves are the result of foliar air pockets, used for cooling the lower surface of the leaves. These air pockets mask the appearance of chlorophyll in the leaves, creating the silver foliar patterns that we enjoy as gardeners. The logical conclusion is that cultivars with more silver in the leaves should be able to tolerate more heat and possibly sun.
A parade of European-bred silver-leaf lungworts soon followed, starting with Pulmonaria saccharata ‘Argentea’, followed by Pulmonaria ‘British Sterling’, then a breakthrough plant in 1998, the introduction of Pulmonaria ‘Majeste’ from Didier Willery of La Ferme Fleurie Nursery in France. This splendid plant would later give rise to another of my favorites, the narrow, all silver-leaf Pulmonaria ‘Samourai’.
Today, the list of silver-leaf lungworts is topped by Pulmonaria ‘Silver Bouquet’, which was bred by Oregon’s Terra Nova Nurseries. In our trials, ‘Silver Bouquet’ makes a scrumptious clump of 1′ long, shiny silver foliage…lovely enough to grow even without flowers. In late winter, the re-emerging silver leaves of Pulmonaria ‘Silver Bouquet’ are topped with clusters of bubblegum-like flowers of blue and pink that hover just above the foliage.
Pulmonaria are short-lived plants by nature and the only way to maintain them on a long-term basis is to divide the clumps every 3-5 years. I like to do this in fall and winter, when the entire clump can be lifted, teased apart, and replanted. Actually, any season you have time to divide the plant will work. In the garden, pulmonarias prefer moist, well-drained soil that is rich in organic matter. While lungworts are quite drought tolerant, a consistently dry soil doesn’t give the best long-term results.
I have also found that light shade with a few hours of morning sun is preferable. While lungworts will grow for a short time in very dark settings, this is not the ideal condition for best performance. I hope you’ll give a breath of silver freshness to your woodland with the addition of some beautiful lungworts.
– Tony Avent