Creeping Jacob's ladder
Polemonium reptans · Polemoniaceae
A low, native Jacob's ladder with loose clusters of pale blue bells in spring over a mound of ladder-like leaves. It does not creep, despite the name.
- Size
- 14 in tall, 16 in wide
- Zones
- 3 to 8
- Light
- Part sun to shade
- Flowers
- Late April to late May
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around creeping Jacob's ladder
The planner designed this bed around creeping Jacob's ladder 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 creeping Jacob's ladder stands where it does.
The plants
- 1 Creeping Jacob's ladder × 6, blue
- 2 Woodland strawberry × 15, white
- 3 Lungwort × 5, pink
- 4 Northern sea oats × 5, tan
- 5 Foxglove × 3, purple
- 6 Inkberry 'Gem Box' × 1, dark green leaves
- 7 Fumewort × 5, pink
Why this plant
- The only bells. The others are open bowls, dense clusters, airy sprays and others. Shape reads at a distance, where colours blur.
- The only blue.
Why here
- In the middle. At 14 in it stands ahead of inkberry 'Gem Box' (2½ ft) without hiding it.
- A step in the back row. Next to inkberry 'Gem Box' (2½ ft) and northern sea oats (3½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 6 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for six weeks. From late April to late May.
- Part of the bed's peak. With lungwort and fumewort in late April: 3 kinds at once. No week has more.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 48% of the planted ground. The most in flower at one time is 3 kinds, from late April. The flowers stay on the cool side of the palette: blue, pink, purple, white and tan.
The planner's own design check: 11 Excellent, 5 Good, 1 Satisfactory. It flags one thing to watch: Foxglove is highly poisonous to people, dogs, cats and horses. Northern sea oats spreads aggressively.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where creeping Jacob's ladder goes in a border
At 14 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
More tolerant of heat than the European Jacob's ladder. The ferny mound stays fresh through summer if the soil is moist.
- Native woodland gardens
- Fine foliage among bold hostas
- Spring flowers for early bees
What to plant with creeping Jacob's ladder
Plants recorded as good partners for it, and what each pairing does:
- Foamflower: in flower together for six weeks, from late April; spires rising out of its mound; happy in the same moist soil.
- Wild geranium: in flower together for five weeks, from early May; happy in the same moist soil.
- Christmas fern: its dark green leaves are a setting for the flowers, before and after.
Questions about creeping Jacob's ladder
Does creeping Jacob's ladder need sun or shade?
Creeping Jacob's ladder grows in part sun (4 to 6 hours of sun, including some afternoon sun), 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 creeping Jacob's ladder grow in?
USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does creeping Jacob's ladder flower in my zone?
In zone 5 it flowers late April 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 | Early May to mid June |
|---|---|
| Zone 4 | Early May to early June |
| Zone 5 | Late April to late May |
| Zone 6 | Mid April to late May |
| Zone 7 | Mid April to mid May |
| Zone 8 | 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 creeping Jacob's ladder be planted?
12 in (30 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 16 in (40 cm), so a group knits into one patch.
It grows 14 in (35 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many creeping Jacob's ladder plants do I need?
At 12 in apart, set out in staggered rows:
- 12 to fill 10 square feet (about 1 m²)
- 11 for a single row 10 ft (3 m) long
- 38 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 six in one group.
Is creeping Jacob's ladder poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat creeping Jacob's ladder?
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 creeping Jacob's ladder?
Creeping Jacob's ladder is over by late May. These start as it finishes and carry the same spot on, so it never goes flat:
- Lady's mantle: from late May to early July, 18 in tall.
- Astilbe: from late June to mid July, 24 in tall.
- Carpathian bellflower 'Blue Clips': from late June to late August, 8 in tall, to stand in front of it and cover its fading stems.
What does creeping Jacob's ladder look like in winter?
Creeping Jacob's ladder dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
Is creeping Jacob's ladder good for bees and butterflies?
Creeping Jacob's ladder is visited by bees.
It is native to the United States and Canada.
More Polemonium
- Jacob's ladder Polemonium caeruleum
- Jacob's ladder 'Stairway to Heaven' Polemonium reptans 'Stairway to Heaven'
In these guides
- Pet-safe plants for shade
- Native perennials for pollinators
- Native plants for shade
- Garden plants native to Canada
- Plants for bees
- Plants with blue flowers
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
Every fact on record
- Type
- Perennial
- Size
- 14 in (35 cm) tall, 16 in (40 cm) wide
- Plant
- 12 in (30 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Late April to late May; hanging bells; blue
- Leaves
- Fine texture, herbaceous; green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 3 to 8
- Light
- Part sun, part shade, shade
- Soil
- Rich, evenly moist
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Polemoniaceae
- Comes from
- Northern America
- Attracts
- Bees
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.