Solomon's seal
Polygonatum biflorum · Asparagaceae
Arching, unbranched stems with leaves arranged like a ladder, and pairs of small, greenish-white bells hanging beneath in spring. Blue-black berries follow, and gold autumn colour.
- Size
- 3 ft tall, 24 in wide
- Zones
- 3 to 9
- Light
- Part shade to shade
- Flowers
- Early May to late May
- Pets
- Toxic (mild)
- Job in a bed
- Drift
A bed built around Solomon's seal
The planner designed this bed around Solomon's seal when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, part shade. It chose the other plants from the 513 that suit those conditions, and says below why Solomon's seal stands where it does.
The plants
- 1 Solomon's seal × 5, white
- 2 Leadwort × 16, blue
- 3 Moor grass 'Greenlee' × 5, tan
- 4 Tall astilbe 'Superba' × 3, purple
- 5 Inkberry 'Gem Box' × 1, dark green leaves
- 6 Celandine poppy × 3, yellow
- 7 Hardy cyclamen × 8, pink
Why this plant
- The only bells. The others are dense clusters, spires, plumes and others. Shape reads at a distance, where colours blur.
- The only white. White sits between stronger colours and calms them.
Why here
- Anchors a back corner. At 3 ft it is one of the taller plants here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to tall astilbe 'Superba' (4 ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 5 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for five weeks. From early May to late May.
- Part of the bed's peak. With moor grass 'Greenlee' and celandine poppy in mid May: 3 kinds at once. No week has more.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 45% of the planted ground. Tall astilbe 'Superba' and Solomon's seal anchor the back corners of the bed: the tallest plants on the plan stand there. The bed is balanced: the left half carries 53% of the visual weight and the right half 47%.
The planner's own design check: 14 Excellent, 3 Good. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where Solomon's seal goes in a border
At 3 ft it belongs in the middle of a bed. In the planner's ten height classes it is medium tall (2½ to 3 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
The arching stems are a shape no other shade plant offers, and they contrast with the mounds of hostas and the upright fronds of ferns. It spreads slowly into a colony.
- Arching form in shade
- Native woodland gardens
- Dry shade once established
What to plant with Solomon's seal
Plants recorded as good partners for it, and what each pairing does:
- Hosta: its green leaves are a setting for the flowers, before and after; bold leaves against its medium ones; low enough (18 in) to stand in front of it.
- Christmas fern: its dark green leaves are a setting for the flowers, before and after; low enough (20 in) to stand in front of it.
- Wild ginger: its green leaves are a setting for the flowers, before and after; bold leaves against its medium ones; low enough (6 in) to stand in front of it.
Questions about Solomon's seal
Does Solomon's seal need sun or shade?
Solomon's seal grows in part shade (2 to 4 hours of sun, mostly in the morning) and shade (less than 2 hours of direct sun, or bright dappled light).
It wants soil that stays evenly moist, rich in organic matter, and a good soak in dry spells.
What zones does Solomon's seal grow in?
USDA zones 3 to 9. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does Solomon's seal flower in my zone?
In zone 5 it flowers early May to late May. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 3 | Mid May to mid June |
|---|---|
| Zone 4 | Early May to early June |
| Zone 5 | Early May to late May |
| Zone 6 | Late April to late May |
| Zone 7 | Mid April to mid May |
| Zone 8 | Mid April to early May |
| Zone 9 | Early April to early May |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should Solomon's seal be planted?
18 in (45 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 24 in (60 cm), so a group knits into one patch.
It grows 3 ft (90 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many Solomon's seal plants do I need?
At 18 in apart, set out in staggered rows:
- 5 to fill 10 square feet (about 1 m²)
- 7 for a single row 10 ft (3 m) long
- 17 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used five in one group.
Is Solomon's seal poisonous to dogs?
Yes: mild toxicity to people and dogs. The berries can cause vomiting and diarrhoea if eaten.
It is not recorded as toxic to cats, but it is to people.
Rated from NC State Extension. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like Solomon's seal?
These come closest to doing what Solomon's seal does, and no toxicity is recorded for them:
- False Solomon's seal: the same job in a bed, the same flowering time and the same colour; 6 in shorter.
- Wild geranium: the same job in a bed and the same flowering time; 16 in shorter, pink, not white.
- Columbine meadow rue: the same job in a bed, the same size and the same colour; flowers late May to late June, fine leaves, not medium.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
Do deer eat Solomon's seal?
They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.
What flowers after Solomon's seal?
Solomon's seal is over by late May. These start as it finishes and carry the same spot on, so it never goes flat:
- Astilbe: from late June to mid July, 24 in tall, to stand in front of it and cover its fading stems.
- Lady's mantle: from late May to early July, 18 in tall, to stand in front of it and cover its fading stems.
- Foxglove: from early June to mid July, 4 ft tall.
What does Solomon's seal look like in winter?
Solomon's seal dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.
Is Solomon's seal good for bees and butterflies?
Solomon's seal is visited by pollinators, butterflies and songbirds.
It is native to the United States and Canada.
More Polygonatum
- Dwarf Solomon's seal Polygonatum humile
- Variegated Solomon's seal Polygonatum odoratum var. pluriflorum 'Variegatum'
In these guides
- Plants for slopes and banks
- Garden plants toxic to dogs
- Native perennials for pollinators
- Native plants for shade
- Garden plants native to Canada
- Plants for butterflies
- Plants that feed garden birds
- Plants for a white garden
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
In flower in: May
Every fact on record
- Type
- Perennial
- Size
- 3 ft (90 cm) tall, 24 in (60 cm) wide
- Plant
- 18 in (45 cm) apart
- Height class
- Medium tall (2½ to 3 ft)
- Place in the bed
- Middle
- Flowers
- Early May to late May; hanging bells; white
- Leaves
- Medium texture, herbaceous; green
- Shape
- Arching, spreading
- Hardy in
- USDA zones 3 to 9
- Light
- Part shade, shade
- Soil
- Rich, evenly moist
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Asparagaceae
- Comes from
- Eastern North America, North Carolina
- Attracts
- Pollinators, butterflies, songbirds
- Stands up to
- Erosion
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.