Iris tectorum
Japanese roof iris
An upright perennial, to around 40cm high, with fans of sword-shaped, ribbed green leaves. Flowers are pale violet streaked with purple, or occasionally white, with strongly ruffled edges to both standards and falls
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Neutral, AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple White | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or East–facing or West–facing
Exposure
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
- China
How to grow
Cultivation
Grow in well-drained, fertile, neutral to slightly acid soil in full sun
Propagation
Propagate by division, see dividing iris for more detailed advice
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Flower borders and beds
- Wall side borders
Pruning
Remove spent flower stems in summer, and any dying foliage in autumn
Pests
Diseases
May be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases
Get involved
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