Iris prismatica
An upright perennial, to around 70cm high, with slender rhizomes spreading to form clumps of narrow, grass-like green leaves. Flowers have violet blue standards, and narrow falls with white throats. Native to swamps and salt marshes and named for the angular shape of the seed capsules
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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, Poorly–drainedpH
Neutral, AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple Blue White | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
South–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
- United States
How to grow
Cultivation
Thrives in moist, humus rich, ideally neutral to slightly acid soil. Will tolerate part shade but flowering is best in full sun. Suitable for planting at the edges of ponds and streams, in a bog garden, or in a border where the soil does not dry out
Propagation
Propagate by division, see dividing iris for more detailed advice
Suggested planting locations and garden types
- Cottage and informal garden
- Flower borders and beds
Pruning
Remove spent flower stems after flowering, and any dying foliage in autumn
Pests
May be susceptible to aphids, slugs, snails, thrips and iris sawfly
Diseases
May be susceptible to aphid-borne viruses and grey moulds; see Iris diseases
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