Growing Siberian Iris: Easier Than Bearded Iris with Delicate Beauty

When you hear "iris," do you picture a big bearded beauty above swordlike leaves? That's bearded iris (Iris germanica), a popular spring/summer star. The Siberian iris (I. sibirica) is a different flower entirely, well worth your attention.

Easier to grow than I. germanica with very little care, I. sibirica has no beard but is beloved for delicate flowers and soft, grasslike foliage.

Siberian iris generally grows 2–4 feet tall; withstands wind, rain, and cold; and makes a lovely cut flower. Impressively, one mature plant can send out 20+ flower stems at once, blooming from late April to early summer. It quickly fills sunny borders and works well at corners. Good companions: aquilegia, daisies, lupines, peonies, phlox, and pinks.

Best Conditions for Iris

Siberian iris grows well in USDA Zones 2–9. In northern regions, full sun. In warm seasons, light shade is fine. In extremely hot southern climates, grow in shade. Tolerates dry periods but performs best with perennials watered well all summer.

How to Plant Iris

Plant rhizomes with crowns 1 inch below soil level, covered with soil—2 inches deep if sandy. To avoid air pockets, make a small soil hill in the planting hole center, place rhizome on hill with roots spread around, fill hole, pack tight. Keep evenly moist 6–8 weeks after planting.

Photo: Anna bogush/shutterstock

Ensure a Long Season

For longest bloom period, include early and late varieties:

Early Bloomers:

• 'Bouquet'
• 'Indy'
• 'Pleasures of May'

Late Bloomers:

• 'King of Kings'
• 'Liberty Hills'

For Best Iris Blooms

Remove spent flowers after bloom to prevent seed heads. In late fall, cut foliage to ground and mulch well after ground freezes.

After a few years, divide large clumps to ensure continued bloom. Dig mature plants in spring/early summer after bloom or early fall before frost. Loosen soil carefully, pry rhizomes loose with rocking motion. Cut with sharp knife, leaving each piece with two fan divisions. Plant divisions, cover with soil 1–2 inches deep, keep evenly moist 6–8 weeks.

Photo: Michael thaler/shutterstock

The Top 12 Siberian Iris Varieties

• Siberian irises come in purple, blue, pink, lavender, yellow, white, and bi-/tritones. Society for Siberian Irises members' top picks: 'Roaring Jelly', 'Over in Gloryland', 'Jewelled Crown', 'Strawberry Fair', 'Coronation Anthem', 'Shaker's Prayer', 'Lady Vanessa', 'Sultan's Ruby', 'Lake Keuka', 'Mesa Pearl', 'Pink Haze', 'Somebody Loves Me'.

Iris: What's in a Name?

In Greek mythology, Iris is the rainbow goddess. The iris bloom symbolized monarchs and royal families throughout history. Earliest iris painting is a fresco in King Minos's palace on Crete (2100 BC).

Bourbon kings of France, including Louis XIV, adapted the iris on royal banners as the "fleur-de-lis."

Iris is Tennessee's state flower; fleur-de-lis is New Orleans' emblem.