Solomon’s seal (Polygonatum) is an elegant woodland plant that is native to North America. Although the dangling, white flowers and the black seed pods that follow are charming, it’s the arching stems and foliage that make Solomon’s seal such a favorite in shade gardens and woodland settings. Once established, Solomon’s seal slowly spreads out and creates a nodding blanket of foliage that turns a golden yellow in autumn.
Solomon's Seal Basics
- Leaves: The slender, arching stems of Solomon's seal have alternating lance-shaped leaves that are either green or tipped with white.
- Flowers: Small, tubular, white flowers dangle underneath the leaves. The species name of P. biflorum refers to the fact that the flowers grow in pairs along the leaf axils. Solomon's seal will bloom in mid-spring to early summer. The black seed pods that follow will persist into summer. More mature plants tend to have more profuse flowers and are a bit showier. But it’s the plant form rather than the flowers that makes Solomon’s seal such an interesting plant.
- USDA Hardiness Zone: Solomon's Seal is reliably perennial in USDA Hardiness Zones 3 through 9. They are easy growers, but somewhat slow to become established. Another big plus is that Solomon’s seal is deer resistant.
Size will vary among the different species and cultivars. Most Solomon's seal plants grow to about 1 to 2 feet tall. The width of the plant is really only the 3- to 5-inch leaf span, but since the stem arches up and over, the width is more like 1 to 3 feet. There is a giant Solomon's seal (Polygonatum biflorum var. commutatum) that tops out at about 5 feet tall and really makes a statement in the garden.
These really are woodland plants. Give your Solomon's a spot in partial shade. Solomon’s seal can only take sun if the climate is cool and the soil is moist.
Using Solomon's Seal in Your Garden Design
Solomon’s seal looks best when allowed to naturalize in a woodland setting. It pairs well with many shade garden plants, like Brunnera (Siberian bugloss), cranesbill geranium, Dicentra ( bleeding heart), Epimedium (barrenwort), ferns, hellebore, Heuchera (coral bells) and Tiarella (foamflower). These plants have attractive and often colorful foliage, providing season-long interest.
Suggested Solomon's Seal Varieties to Grow
Try your green thumb at these varieties:
- True Solomon’s Seal (P. biflorum): Very dependable and one of the fastest growing.
- Fragrant Solomon's Seal (P. odoratum "Variegatum"): Variegated form with white tips.
- Fragrant Solomon's Seal (Polygonatum. biflorum var. commutatum): Grows to about 5 feet in height.
Solomon's Seal Growing Tips
Plants are usually started by transplants or rhizomes. Seeds of Solomon’s seal can take up to two years to sprout, so you will get some self-sowing in established plantings, but you will need a lot of patience to start your own plants from seed.
Solomon’s seal likes a rich organic soil with a soil pH in the acidic to neutral zone. They need some shade to truly thrive. Damp shade is even better, although once established, they are quite drought tolerant. Plants can be started in the spring or fall. Plant only 1 to 2 inches deep and about 2 to 3 inches apart.
Caring for Your Solomon's Seal Plants
Solomon’s seal seldom needs division. It takes several years before a clump is large enough to divide for propagation purposes. When ready, divide in early spring or fall and leave several buds on each division, for the best success. The rhizomes can be divided even further, but it will take longer for them to become established. Another option is to remove and plant just the offsets at the out edges of a clump.
Solomon’s seal does not require deadheading. The flowers are small and will drop off naturally. The foliage remains attractive all season, so the plant is virtually maintenance free. The stems even disconnect from the rhizomes on their own, after frost. But before that, the foliage turns a nice golden yellow in fall.
Pests and Problems
Healthy Solomon’s seal plants growing in good conditions seem to have few problems. If the weather is extremely damp, you may see signs of powdery mildew or another fungal disease. These should ameliorate as things dry out. Better air circulation will also help. Slugs and snails can also become a problem in damper areas.