Leadwort may not sound like a flattering name, but this pretty, hardworking perennial still deserves a place in your garden. Prized for its tolerance of tough growing conditions, droughty soil, deer, and all sorts of pests, the clean green foliage and bright blue flowers, along with its fiery fall colors, all make leadwort a desirable garden plant. Fast-growing but not invasive, leadwort is often used as a groundcover or spreading perennial for the front of a bed.
Leadwort Overview
Where to Plant Leadwort
Plant leadwort in a location with full or partial sun and soil that is well-drained and acidic to slightly alkaline soil. Leadwort is slow to emerge from winter dormancy, which makes it a wonderful companion for spring bulbs. As tulips, daffodils, and hyacinths finish blooming, leadwort emerges from the soil and unfurls new leaves. The plant's glossy green leaves cover up the withering bulb foliage. The purple-blue flowers of leadwort are pretty partners for yellow-flowered perennials such as yarrow and coreopsis.
Embrace the spreading habit of this plant and use it as a groundcover in a shrub border or foundation planting. Not only will leadwort choke out weeds, but it will also provide a splash of floral color in summer and bright red foliage in fall.
How and When to Plant Leadwort
Plant leadwort after the last average frost date in your location. Dig a hole about twice the diameter of the nursery container. Fill the hole and tamp down the soil. Water it well and keep the soil moist until the plant is established.
Space plants 8 to 12 inches apart, or if you want to cover an area faster, plant it every 8 inches.
Leadwort Care Tips
Leadwort does not require much care. In suitable conditions, it grows fast and reaches its mature size within six months to one year.
Light
Plant leadwort in full sun or part shade. Afternoon shade that protects the plant from the hot sun is best.
Soil and Water
Sandy and loamy soils are ideal but plumago is no finicky about soil texture as long as it is well-drained. It is also not particular about soil pH and thrives in a range between 6.1 and 7.5. Leadwort overwinters best when planted in well-drained soil; wet or boggy soil is particularly troublesome in winter.
Temperature and Humidity
Leadwort is marginally hardy in Zone 5. To help it survive the winter, spread a thick layer of insulating mulch over the plants in late fall and rake it away in spring. The plant tolerates heat well and is not bothered by high humidity.
Fertilizer
In the spring, add a slow-release, high-nitrogen fertilizer, such as 12-6-6 and again in early summer to spur growth for a quick groundcover. For the amount to use, follow product label directions.
Pruning
There is no need to prune leadwort during the growing season or in the fall; in fact, it is even recommended to leave the old stems standing over the winter to mark the location because leadwort is late to break dormancy. Cut the stems back in the spring to make room for new growth.
Potting and Repotting Leadwort
Select a pot with large drainage holes that fits the root ball plus at least 2 inches to accommodate future growth. Fill it with a combination of potting mix and compost. Keep in mind that potted plants need more frequent watering and fertilization than inground plants.
While leadwort is hardy to zone 5, potted plants need some protection during the winter, as the roots are exposed to the cold. Wrap the container in bubble wrap or burlap, or place it in a larger container and fill the space between the two containers with mulch for insulation.
Repot the plant to a large pot with fresh potting mix when it has outgrown its container.
Pests and Problems
Leadwort has no serious disease or pest problems. It might get powdery mildew and mealybugs.
How to Propagate Leadwort
Division is the easiest way to propagate leadwort. If the plant grows out of bounds, divide it in the spring, just after new growth emerges. Dig up the entire roots and cut the clump into sections. Replant the sections at the same depth as the original plant and backfill the planting with soil. Keep the new plants well-watered until they have recovered from the transplant shock and you see new growth.
Leadwort Companion Plants
Bluebeard
Offering rare blue late-season flowers, bluebeard grows into a compact and flattering companion to other late bloomers such as asters and black-eyed Susans. The wispy bunches of flowers develop along the stems in midsummer to early fall. Silvery bluebeard foliage adds a little extra shine to the landscape. A plethora of new varieties are available, including those with variegated green and white leaves, gold leaves, and pink flowers.
Small-Cup Daffodils
Small-cup daffodils have all the same qualities as large-cup and trumpet daffodils, with the exception of the size of their cups. To be classified as a small-cup daffodil, the cup must be less than one-third the length of the petals. Most small-cup daffodils bear only one flower per stem. Blooms may be yellow, white, pink, or bicolor, and some are fragrant. Daffodils make good cut flowers. Plants may be full-size or miniature. All varieties in this class are deer- and rabbit-resistant.
Species Tulips
If you want long-lived tulips, pick the species types. These include wild varieties and selections developed from those species. Most are smaller in stature and bloom size than hybrid tulips. Because they are variants of wildflowers, species tulips are usually long-lived, hardy, and withstand stormy spring weather conditions. Many multiply and spread from year to year. Species tulips are especially suited for growing in rock gardens or tucked into beds and borders. Many open only in sunny conditions, keeping their blooms closed on cloudy days or in the evening.
Frequently Asked Questions
- Are there different types of leadwort?In addition to C. plumbaginoides, there are some lesser-known species, including Chinese leadwort (C. willmottanium) and Burmese leadwort (C. griffithii), but they are rather rare and not commonly sold by nurseries.
In addition to C. plumbaginoides, there are some lesser-known species, including Chinese leadwort (C. willmottanium) and Burmese leadwort (C. griffithii), but they are rather rare and not commonly sold by nurseries.
- Is plumbago the same as leadwort?The nomenclature is a bit confusing because two members of the leadwort family— Ceratostigma and Plumbago—are both commonly called leadwort and plumbago but they are different genera. The Ceratostigma genus comprises eight species that are native to Africa and Asia. The Plumbago genus includes wild leadwort (Plumbago zeylanica), which is native to North America.
The nomenclature is a bit confusing because two members of the leadwort family— Ceratostigma and Plumbago—are both commonly called leadwort and plumbago but they are different genera. The Ceratostigma genus comprises eight species that are native to Africa and Asia. The Plumbago genus includes wild leadwort (Plumbago zeylanica), which is native to North America.