Polemonium archibaldiae
towering Jacob's ladder
A bushy, clump-forming perennial to around 1m high, with long, pinnate leaves, divided into up to 30 lance-shaped leaflets held in offset pairs. Bell-shaped flowers, usually violet-blue but sometimes white, are produced in loose clusters on upright stems, from late spring through to late summer or early autumn. White-flowered varieties are often scented
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Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | White Purple | Green | ||
|---|---|---|---|---|
| Summer | White Purple | Green | ||
| Autumn | White Purple | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Polemoniaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Genus
Polemonium can be annuals or herbaceous perennials or upright or spreading habit, with pinnate leaves and usually clustered, tubular, bell, or funnel-shaped flowers
- Name status
Correct
How to grow
Cultivation
Grow in fertile, moist but well-drained soil, will benefit from some shade where summers are hot
Propagation
Propagate by seed, sown in containers in a cold frame in autumn or spring, or by division in spring
Suggested planting locations and garden types
- Cottage and informal garden
- Gravel garden
- Wildflower meadow
- Banks and slopes
- Flower borders and beds
Pruning
Deadhead regularly to encourage new flowers
Pests
Generally pest-free
Diseases
May be susceptible to powdery mildews
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