Iris ensata
Japanese water iris
An herbaceous perennial to 80cm in height, forming a dense clump of erect foliage, with rich violet-purple flowers 10-12cm in width in mid summer, the broad, rounded falls each with a small white or yellow midrib
Synonyms
Iris kaempferi
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Poorly–drainedpH
AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple | Green | ||
| Autumn | ||||
| Winter |
Position
- Full shade
- Partial shade
Aspect
South–facing or East–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Iridaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling. Pets: Harmful if eaten. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Iris may be rhizomatous or bulbous perennials, with narrow leaves and erect stems bearing flowers with 3 large spreading or pendent fall petals, alternating with 3 erect, often smaller, standard petals, in late winter, spring or early summer
- Name status
Correct
- Plant range
- E Asia
How to grow
Cultivation
Grow in moist to wet, deep, humus-rich, acid soil; it thrives at the margins of ponds or streams
Propagation
Propagate by division of rhizomes from midsummer to early autumn
Suggested planting locations and garden types
- City and courtyard gardens
- Coastal
- Cottage and informal garden
- Flower borders and beds
- Wall side borders
Pruning
Remove any dying foliage in autumn, old flower stems can be cut down after flowering
Pests
Diseases
May be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases
Get involved
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