Japanese iris, also called blood iris, is an East Asian iris closely related to the Siberian iris; in the United States it isn't a native wildflower but is grown as a garden perennial, often beside ponds or in rain gardens. Its slender stems hold blue-violet flowers with fine purple veining on the drooping outer petals. It's native to Japan, Korea, northeastern China, Mongolia, and eastern Siberia.
Appearance
- Growth form
- A clump-forming perennial that spreads by , with leaves and unbranched flower stems about 1–3 ft (30–90 cm) tall.
- Flowers
- Two or three flowers per stem, each 2.5–3 in (6–8 cm) across, in reddish purple to blue-violet, rarely white. The are white veined and edged with blue-violet.
- Flowering time
- Late spring to early summer.
Look-alikes
Where it lives
- Typical habitats
- meadows
- stream and lake edges
- forest margins
- Range
- Native to eastern Asia. In the United States it's a garden plant, not a native wildflower.
Growing it
- Care
- Grows in USDA Zones 4–9. Give it full sun to light shade and consistently moist, well-drained, neutral to acidic soil. Divide clumps as needed. Unlike the related yellow flag iris, it isn't considered invasive.
- Toxicity
- The rhizomes and leaves are toxic if eaten, causing stomach pain and vomiting, and the sap can irritate skin. It's also listed as a problem plant for dogs, cats, and horses.
Name and classification
- About the name
- A 2020 study found no clear way to separate this species from Siberian iris (Iris sibirica) and merged the two, but many references still keep it separate. Some garden plants are sold under either name.
- Varieties and forms
- 'Snow Queen' is a white-flowered selection collected in Japan and introduced in 1900.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
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