What soil does Siberian iris grow in?

It tolerates these soils: average garden soil, clay, acidic.

Is Siberian iris hardy?

Hardy down to -40 °C (USDA zone 3, RHS H7). It gets through winter in every part of the country.

Is Siberian iris toxic to children?

Yes, it is mildly toxic to children.

When does Siberian iris flower?

Flowering: May–June, blue, purple, white.

How much water does Siberian iris need?

Water need: medium. Drought tolerance: medium.

How much does Siberian iris cost?

It sells for roughly €5.90 to €13 in local shops, depending on size.

Siberian iris

Iris sibirica

Siberian iris (Iris sibirica) is a perennial. Light: full sun, part shade. Hardy down to -40 °C. Drought tolerance: medium. Toxic to dogs and cats, mildly toxic to children. Sold in local shops from about €5.90.

Illustration of Siberian iris — An illustration of the typical shape of the mature plant, not a photo.

What it's good for, and what it isn't

A graceful iris with grassy leaves that carries blue, purple or white flowers on tall stems in May and June, and keeps a handsome, grass-like clump of foliage after bloom. It suits sun or light part shade and moist soil, tolerates pond margins and occasionally wet ground, and gets through shorter dry spells once established. Divide it when the centre of the clump goes bare and flowering drops.

Watch out for

The species is native to Central Europe and protected in the wild: it must not be dug up or collected, so plant only nursery-propagated stock. The troubles of bearded irises (rhizome rot, leaf spot) seldom affect it; slugs sometimes feed on young shoots. In hot, dry summers it suffers without watering and flowers less. After a few years the centre of the clump dies out, so divide it after flowering or in early autumn. In too much shade the foliage flops.

Key facts

Light: Full sun, Part shade
Water need: Medium
Care: Low
Size after 10 years: 90 cm × 75 cm
Hardiness: down to -40 °C
Foliage: Deciduous
Flowering: J F M A M J J A S O N D May–June, blue, purple, white

Group	Perennial
Light	Full sun, Part shade
Size after 10 years	90 cm × 75 cm
Ultimate size	0.6–1.2 m × 60–90 cm
Hardiness	down to -40 °C (USDA 3, RHS H7)
Soil	Average garden soil, Clay, Acidic
Foliage	Deciduous
Flowering	May–June, blue, purple, white
Water need	Medium
Drought tolerance	Medium
Maintenance	Low
Root aggressiveness	Low
Suckering	no data
Spreading	Low
Distance from buildings	no data
Distance from paving	no data
Litter	not typical
Planting distance	45 cm
For dogs	Toxic
For cats	Toxic
For children	Mildly toxic
Typical price	from about €5.90

Toxicity data is for information only. If your pet or child has eaten a plant, contact a vet or a doctor.

Sizes and prices available

The same plant is sold as a small pot and as a specimen several metres tall, and the price follows. Prices are rounded and for guidance only.

Size	Typical price
11 cm	approx. €6.90
30-40 cm	approx. €7.50
30+ cm	approx. €8
30-50 cm	approx. €10
3,040 cm	approx. €7.50
size not stated	approx. €5.90 – €13

Frequently asked questions

Data updated: October 8, 2026 · How our data is made

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