Siberian iris: planting, dividing and storing the rhizome

Store	Rhizome. Grows horizontally and is segmented, with a shoot at the growing tip.
Depth	2-3 cm to the base of the rhizome
Spacing	45-60 cm apart
When	Divide and replant after flowering (late summer). Divide and replant: 10 weeks to 4 weeks before your first autumn frost. Work out your dates.
Pets	Toxic to Dogs, Toxic to Cats, Toxic to Horses (ASPCA)

Store

Rhizome. Grows horizontally and is segmented, with a shoot at the growing tip.

Depth

2-3 cm to the base of the rhizome

Spacing

45-60 cm apart

When

Divide and replant after flowering (late summer). Divide and replant: 10 weeks to 4 weeks before your first autumn frost. Work out your dates.

Pets

Toxic to Dogs, Toxic to Cats, Toxic to Horses (ASPCA)

About Siberian iris

A clump-forming iris with a thin dense rhizome that likes moist soil and flowers well in full sun.

Depth and spacing

Typical range: 2-3 cm deep and 45-60 cm apart. A general rule is to plant at two to three times the height of the rhizome; check the label for your variety. The drawing is to scale for 2.5 cm deep and 52.5 cm apart (the size of the organ is illustrative); try your own measurements.

When to plant

Divide and replant after flowering (late summer). Divide and replant: 10 weeks to 4 weeks before your first autumn frost. These are rules of thumb for the northern hemisphere. Enter your frost dates for real dates.

Dividing and propagating

Divide congested clumps in early autumn or late summer with a sharp spade or knife; replant divisions with the rhizome just under the surface.

Lifting and storing

Not stored; replant at once.

Toxic to Dogs, Toxic to Cats, Toxic to Horses

The ASPCA lists Iris species as: toxic to dogs, toxic to cats, toxic to horses. Toxic principle: Pentacylic terpenoids (zeorin, missourin and missouriensin). Signs: Salivation, vomiting, drooling,lethargy, diarrhea. Highest concentration in rhizomes. If your pet has chewed any part, call your vet or an animal poison helpline. ASPCA entry.