Iris stolonifera
stolon-spreading iris
A rhizomatous herbaceous perennial, 30-60cm high, with prominently-veined blue-green leaves 0.5-1.5cm wide, and flowers 8cm across in late spring or early summer. Flowers vary in colour from pale lilac to deep brownish-purple, the falls darker than the standards; both standards and falls are veined, and flushed at the edges, with purple or brown; the beards are white, cream, yellow or blue; it is dormant in late summer
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Blue | Brown Cream Purple White Yellow | Green Blue | |
|---|---|---|---|---|
| Summer | Green Blue | Brown Cream Purple White Yellow | Green Blue | |
| Autumn | Green Blue | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
ShelteredDrought resistance
Yes Hardiness
H4Botanical details
- Family
- Iridaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling
- 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
Unresolved
- Plant range
- C Asia
How to grow
Cultivation
Grow in very well-drained soil, in full sun, and with the top surfaces of the rhizomes exposed so that they get baked in summer sun, which encourages flowering; best grown in a bulb frame in containers using gritty, free-draining compost, and kept dry during late summer and winter; may be grown outside in a well-drained sunny site on a bank or in front of a sunny wall, if given protection from heavy winter rain
Propagation
Propagate by seed, or by division of rhizomes after flowering; for more advice, see dividing irises
Suggested planting locations and garden types
- City and courtyard gardens
- Rock garden
- Gravel garden
- Wall side borders
Pruning
Remove old flower stems after flowering, and any dying foliage
Pests
Diseases
May be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases
Get involved
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