Iris germanica 'Immortality'
Iris germanica ‘Immortality’ is a widely grown white tall bearded iris selected for dependable rebloom in many regions. It flowers in late spring and again from late summer into fall where conditions allow. Plants reach about 30 inches with strong, well-branched stems. The blooms are pure white with a soft, sweet fragrance. Choose this cultivar when you want a classic white with a realistic chance of a second show in North America.
At‑a‑glance
- Group/Class: Tall Bearded (TB), reblooming
- Height × spread: 30 in tall × about 24 in wide (76 cm × 60 cm)
- Bloom window: midseason spring with late summer to fall rebloom where conditions permit
- Color & flower form: ruffled pure white with white beard
- Fragrance: 1 trace
- USDA hardiness: zones 3 to 10
- Breeder / Year / Origin: Lloyd Zurbrigg, 1982, USA
- Awards/registration: AIS Award of Merit 1990; Honorable Mention 1986
- Cut-flower notes: strong, well-branched stems; cut in pencil stage for best vase performance
- Pet safety: avoid
How it differs
- Reblooming habit rather than single spring show.
- Pure white color for clean blends and night gardens.
- Shorter stature than many tall bearded varieties.
- Fragrance present but not overpowering.
Strengths
- Rebloom reported widely across many states and provinces.
- Strong stems support good garden display.
- Reliable white that mixes with most palettes.
Care in one minute
- Site: full sun for 6 to 8 hours each day.
- Soil: well drained and lean to neutral or slightly alkaline; keep rhizome tops just at or slightly above the soil surface.
- Water: water to establish and during extended dry spells; avoid waterlogged soil to prevent rot.
- Feeding: apply a low-nitrogen fertilizer such as 5-10-10 in early spring and again just after bloom; keep granules off the rhizomes.
- Grooming: remove spent blooms and cut stalks after flowering; divide clumps every 3 to 5 years.
- Winter: in cold regions cut foliage to 3 to 6 inches in late fall and avoid mulching over rhizomes.
Watch‑outs
- Rebloom depends on climate, fertility, and late-season moisture.
- Avoid deep planting or heavy mulch over rhizomes.
- Susceptible to iris borer and soft rot if stressed.
Best uses (tags)
- borders
- cutting
- reblooming
Provenance note
Introduced by Lloyd Zurbrigg in 1982 and recognized with AIS awards. The AIS Rebloom Checklist lists many reports of fall bloom across North America.
References
- American Iris Society – (TB) ‘Immortality’
- Missouri Botanical Garden – Plant Finder: Iris ‘Immortality’
- Penn State Extension – German Bearded Iris
- ASPCA – Iris toxicity for pets
Written by: Your Flowers Guide editorial team
We are a small independent group of flower lovers who research and review each guide using trusted horticultural and educational sources. Learn more about us