How to Grow Tall Bearded Iris Immortality
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Tall Bearded Iris Immortality
Iris germanica 'Immortality'
flowerImmortality is a remontant (reblooming) tall bearded iris cultivar known for its large, fragrant white flowers with subtle yellow signals on the falls. This award-winning variety produces blooms in spring and again in summer or fall, making it exceptional among iris varieties. It reaches 28-36 inches tall and displays elegant, ruffled petals characteristic of premium bearded iris cultivars.
When should you plant Tall Bearded Iris Immortality in your zone?
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Example Tall Bearded Iris Immortality timeline · Pittsburgh, PA (Zone 6b)
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Plant Tall Bearded Iris Immortality
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Tall Bearded Iris Immortality blooms
Mid-to-late summerBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Tall Bearded Iris Immortality dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Zones 3-9, with best rebloom performance in zones 5-8
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Get my Tall Bearded Iris Immortality timeline →Growth Stages
Dormancy/Emergence
October-March dormancy; emergence in March-April depending on zoneRhizomes lie dormant underground through winter. In spring, green shoots emerge from the rhizome crown.
Ensure excellent drainage to prevent winter rot. Do not mulch heavily over rhizomes. Plant in fall (August-October) for best establishment.
Vegetative Growth
4-6 weeksFan-shaped leaves develop rapidly in spring, reaching full height before blooms appear. Sword-like blue-green foliage creates an attractive architectural structure.
Water moderately if spring is dry. Remove any dead or yellowed leaves. Apply balanced fertilizer (10-10-10) once growth is 4-6 inches tall.
Spring Bloom
2-3 weeks per stem, multiple stems per rhizomeTall flower stems emerge with multiple buds. Large white ruffled flowers with yellow beards open sequentially over 2-3 weeks per stem. Fragrant and long-lasting flowers.
Enjoy the bloom cycle. Deadhead spent flowers but leave stems intact if rebloom is desired. Avoid overhead watering to prevent petal spotting.
Summer Rest & Rebloom Initiation
June-AugustAfter spring bloom fades, foliage remains green. In mid-summer, reduce watering significantly to induce stress and trigger rebloom initiation. New flower buds begin forming in August.
Cut back seed pods if formed (conserves energy). Apply low-nitrogen, high-phosphorus fertilizer (5-10-10) in July to encourage rebloom. Reduce irrigation to trigger flowering cycle.
Rebloom & Fall Flowers
August-October until frostNew flower stems emerge with secondary blooms, though typically fewer and slightly smaller than spring flowers. Same white flowers with fragrance bloom in late August through October depending on zone.
Continue to deadhead. Protect from early frost with light mulch if temperatures drop below 20°F. Stop fertilizing by August 1 to allow hardening off before winter.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Remove and destroy infested rhizomes. Cut back foliage to ground level in fall and remove debris to eliminate overwintering sites. Apply preventative insecticide in spring when foliage reaches 6 inches. Dig and inspect rhizomes in early spring for jelly-like frass evidence.
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Spray foliage with water to dislodge mites. Apply miticide if heavy infestation occurs. Improve air circulation and avoid overhead watering.
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Spray with insecticidal soap or neem oil. Encourage natural predators like ladybugs. Hosing off with water can be effective.
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Remove affected leaves. Ensure good air circulation. Avoid overhead watering. Apply fungicide if severe. Clean up all plant debris in fall.
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Remove and destroy infected rhizomes. Ensure excellent drainage and do not overwater. Do not plant in the same location for 2-3 years.
Uses
Culinary & Beverage Flavoring
CulinaryIris rhizomes, particularly orris root, have a violet-like fragrance and were historically used in teas and liqueurs. Bearded iris flowers are not typically eaten but the rhizomes have aromatic properties used in fragrance industries. [source]
Traditional Herbal Uses
MedicinalHistorically, iris roots were used in traditional medicine for respiratory support and as a diuretic. Modern herbalism occasionally references iris root preparations, though clinical evidence is limited. [source]
Fragrance & Potpourri
HouseholdIris flowers provide fragrance for fresh arrangements and dried arrangements. The rhizomes can be dried and used in potpourri for their violet-like scent that develops over time. [source]
Fresh & Dried Flower Arrangements
CraftTall Bearded Iris Immortality's large ruffled white flowers are prized by florists for spring and fall bouquets and wedding arrangements. The tall sturdy stems and long vase life make them excellent cut flowers. [source]
Pollinator Support
WildlifeIris flowers attract bees and other pollinators with their nectar and pollen. The tall plant structure provides beneficial insect habitat and shelter in the garden. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Cut flowers in the early morning when first blooms open. Cut stems at an angle just above a leaf node, leaving at least one-third of the stem on the plant. Change vase water every 2 days. Flowers last 1-2 weeks in a vase. For landscape enjoyment, deadhead spent blooms to encourage additional stems. Allow spent flowers to drop naturally if saving seed is desired (not necessary for rebloom).
Fun Facts
- 🌱 Immortality is a remontant iris, meaning it reblooms—a rare and highly valued trait. Most tall bearded iris varieties bloom only once in spring, making this cultivar exceptional for providing flowers twice per season.
- 🌱 The iris flower gets its name from the Greek goddess Iris, the personification of the rainbow, because wild iris species display such a wide spectrum of colors.
- 🌱 Tall Bearded Iris Immortality has won multiple prestigious awards including the Dykes Medal from the American Iris Society, the highest honor for iris cultivars.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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