Clematis simsii Sweet
marsh clematis
A deciduous perennial climber with dark green leaves. Masses of lightly fragranced, bell-shaped nodding pale to violet-blue flowers with crinkled edges appear from summer through until autumn. Also works well as ground cover or scrambling through other plants in a herbaceous border if left unsupported
Synonyms
Clematis simsii Sweet
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Size
Ultimate height
1.5–2.5 metresTime to ultimate height
2–5 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple Blue | Green | ||
| Autumn | Purple Blue | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Ranunculaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Climbing
- Potentially harmful
- Skin irritant. Wear gloves and other protective equipment when handling. Pets (rabbits): Harmful if eaten. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Clematis can be deciduous or evergreen shrubs or herbaceous perennials, mostly climbing by twining leaf-stalks, and often with showy flowers. Some have attractive fluffy seedheads in autumn
- Name status
Correct
- Plant range
- SE US
How to grow
Cultivation
Plant in a moisture-retentive, well-drained soil, with the roots and base of the plant kept cool and shaded by other plants or a layer of pebbles at the base. Plant with the crown 5-8cm deep to encourage shoots to grow from below ground level. Good for ground cover if left to scramble through a border, unsupported. See clematis cultivation
Propagation
Propagate by layering or semi-hardwood cuttings
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Climber and wall shrubs
- Flower borders and beds
- Ground cover
- Wall side borders
Pruning
Pests
Diseases
May be susceptible to honey fungus (rarely), clematis wilt and clematis slime flux
Get involved
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