Pulmonaria angustifolia [pul-muh-NARE-ee-ah, an-gus-tee-FOH-lee-uh] is a low-growing perennial plant and member of the pulmonaria genus.
It belongs to the Boraginaceae family, which includes over 2,000 known species.
The plant is an herbaceous perennial, featuring oval leaves with tiny hairs and large clumps of bright blue flowers.
Angustifolia means “narrow-leaved,” which is part of the common name – narrow-leaved lungwort.
People also call it lungwort or blue cowslip, but it’s not related to the real cowslip plant.
If the plant remains in a shaded spot, it should keep coming back each year.
In some regions, people grow the plant as ground cover.
It also makes a great addition to a small balcony.
Pulmonaria Angustifolia Care
Size & Growth
Lungwort can reach up to 18” inches tall, but it typically only reaches about 12” inches with an equal spread.
The plant produces thick clusters of narrow leaves and has relatively thick stems.
Flowering and Fragrance
The narrow-leaf lungwort produces bright blue flowers.
Some of the other varieties of lungwort have red or white flowers.
No matter the color, the flowers have a bell-shaped appearance and don’t produce a notable fragrance.
The plant is typically an early bloomer, producing its flowers in March.
Light & Temperature
Grow the plant outdoors year-round in USDA hardiness zones 5 to 9.
If the plant has shade, it can survive outside during harsh winters.
The shade is an important consideration.
If the plant gets too much sun, the leaves get scorched, and the plant will quickly wither and die.
It also handles a wide temperature range.
If grown indoors, it tolerates lower temperatures in the winter and higher temperatures during the summer.
Watering and Feeding
The plant doesn’t require a lot of attention.
Keep it moist, but avoid soaking it or letting it get too dry.
Use plant fertilizer when dividing the plant. Otherwise, it doesn’t need fertilizer.
It’s a hardy plant growing well in almost any conditions except bright sunlight.
To use fertilizer after division, spread an organic fertilizer over the soil and base of the plant.
Soil & Transplanting
Grow the plant in rich soil with added peat moss. It also requires humus.
Repot the plant each year in the early spring, before it blooms.
To keep the plant looking attractive, remove dead leaves and withered flowers.
How to Propagate Narrow-leaved Lungwort
The best way to propagate lungwort is by division. This allows for fast and easy new growth.
To propagate by division, prepare a new pot or container for the second plant using rich soil with good drainage.
- Carefully remove the mother plant and separate it at the root.
- Plant the new plant in its container and place it in a shaded area.
- Keep it moist until the plant takes root.
- Another option is to take cuttings.
- Take cuttings just as the flowers finish blooming.
- Use thick shoots still mostly green instead of woody.
- Use 2” – 3” inch cuttings with two or three pairs of leaves.
- Remove the leaves near the base of the cuttings and plant them in a short box with propagation soil.
- To make homemade soil, use a combination of compost, peat moss, and sand.
- Cover the container with plastic, and poke holes for ventilation.
- Set the container in a spot with ample sunlight but not direct sunlight.
- The cuttings should take root within four to six weeks.
- Dipping the tips of the cuttings in rooting hormone before planting may speed up the process.
- In fact, they may take root within two to three weeks.
- When the cuttings have grown an inch or two, remove them and place in individual pots or tubs.
Pulmonaria Main Pests or Disease Problems
If kept in a shaded spot, the plant shouldn’t encounter any major pests or disease problems.
When the leaves develop reddish-orange specks, the plant is suffering from rust.
This fungus infects the leaves, turning them yellow before they fall off.
To save the plant, cut away the infected areas.
A fungicide may help stop the spread of the fungus, but this doesn’t always work.
Besides fungus, the plant may develop mildew.
This is common when the plant receives too much moisture.
It may develop powdery mildew on the leaves, causing the foliage to wither and fall off.
Use a fungicide to kill the mildew, and move the plant to an area with more air circulation.
Along with the potential mildew and fungus problems, watch out for the toxicity of the plant.
The stems, leaves, and blooms contain toxic alkaloids.
When ingested, the alkaloids may cause diarrhea, vomiting, lethargy, neurological issues, and even liver damage.
Keep it away from pets and children.
Suggested Narrow-leaved Pulmonaria Uses
The plant grows best in shaded areas and looks great growing under larger plants in a tub.
As a low-growing plant, it also provides suitable cover in a garden bed.