Overview

Iris ensata is a clump forming herbaceous perennial in the genus Iris, part of the Iridaceae family, with deciduous foliage. It typically grows around 0.5-1 metres tall and 0.1-0.5 metres wide, reaching full size in around 2-5 years. Iris ensata grows best in full shade and partial shade, and tolerates clay and loam soils and acid pH. Its UK hardiness is rated H6. Suggested uses include city and courtyard gardens, coastal and cottage and informal garden. It is native to E Asia.

About

Iris ensata is a herbaceous perennial that can reach up to 80 cm tall, developing a compact cluster of upright leaves. In mid-summer, it produces violet-purple blooms measuring 10-12 cm across, featuring broad, rounded falls that display a small white or yellow midrib.

About the genus

Iris can be classified as either rhizomatous or bulbous perennials. They feature slender leaves and upright stems that support flowers characterized by three broad, spreading or drooping fall petals alongside three upright, typically smaller, standard petals. These blooms typically appear in late winter, spring, or early summer.

Growing conditions

Best soil and position for Iris

Sunlight
Full shade, Partial shade
Soil type
Clay, Loam
Soil pH
Acid
Soil moisture
Poorly-drained
Aspect
South-facing, East-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H6

Plant details

Iris ensata size, habit and characteristics

Plant type
Herbaceous Perennial
Habit
Clump forming
Foliage
Deciduous
Height
0.5-1 metres
Spread
0.1-0.5 metres
Time to full height
2-5 years
Suggested uses
City and courtyard gardens, Coastal, Cottage and informal garden
Native to
E Asia
Toxicity
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

Care notes

Pruning and caring for Iris ensata

Cultivation
Grow in moist to wet, deep, humus-rich, acid soil; it thrives at the margins of ponds or streams
Pruning
Remove any dying foliage in autumn, old flower stems can be cut down after flowering
Propagation
Propagate by division of rhizomes from midsummer to early autumn
Pest resistance
May be susceptible to slugs, snails and thrips
Disease resistance
May be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases

Frequently asked questions

How do I grow Iris ensata?

Grow in moist to wet, deep, humus-rich, acid soil; it thrives at the margins of ponds or streams.

Where is the best place to plant Iris ensata?

Iris ensata prefers full shade and partial shade. It suits exposed and sheltered positions.

What soil does Iris ensata need?

Iris ensata grows best in clay and loam soil. It prefers acid soil. Aim for soil that stays poorly-drained.

How do I prune Iris ensata?

Remove any dying foliage in autumn, old flower stems can be cut down after flowering.

How big does Iris ensata grow?

Iris ensata reaches a height of 0.5-1 metres and a spread of 0.1-0.5 metres. It takes around 2-5 years to reach full size.

Is Iris ensata hardy in the UK?

Iris ensata has a UK hardiness rating of H6.

How do I propagate Iris ensata?

Propagate by division of rhizomes from midsummer to early autumn.

Is Iris ensata toxic?

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.