Gladiolus Species, Hardy Gladiolus, Jacob's Ladder, Sword Lily

Gladiolus byzantinus

Family: Iridaceae (eye-rid-AY-see-ee) (Info)
Genus: Gladiolus (GLAD-ee-oh-lus) (Info)
Species: byzantinus (biz-an-TEE-nus) (Info)
Synonym:Gladiolus bornetii
Synonym:Gladiolus communis subsp. byzantinus
Synonym:Gladiolus communis var. byzantinus
» View all varieties of Gladiolus



Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Full Sun



Foliage Color:



18-24 in. (45-60 cm)


3-6 in. (7-15 cm)


USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

Where to Grow:

Unknown - Tell us


Parts of plant are poisonous if ingested

Handling plant may cause skin irritation or allergic reaction

Bloom Color:

Magenta (pink-purple)

Bloom Characteristics:

Unknown - Tell us

Bloom Size:

Unknown - Tell us

Bloom Time:

Mid Spring

Late Spring/Early Summer

Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:

Unknown - Tell us

Propagation Methods:

By dividing rhizomes, tubers, corms or bulbs (including offsets)

From seed; sow indoors before last frost

From seed; direct sow after last frost

Seed Collecting:

Bag seedheads to capture ripening seed

Allow pods to dry on plant; break open to collect seeds


This plant is said to grow outdoors in the following regions:

Vincent, Alabama

Ozone, Arkansas

Paris, Arkansas

Idyllwild, California

Gainesville, Florida

Braselton, Georgia

Moreland, Georgia

Algonquin, Illinois

Winnetka, Illinois

Olathe, Kansas

Carlisle, Kentucky

Baton Rouge, Louisiana

Bordelonville, Louisiana

Doyline, Louisiana

Elm Grove, Louisiana

Springfield, Massachusetts

Florence, Mississippi

Panama, New York

Aulander, North Carolina

Elizabeth City, North Carolina

Raleigh, North Carolina

Florence, South Carolina

Saint Helena Island, South Carolina

Memphis, Tennessee

Burleson, Texas

Colmesneil, Texas

Dallas, Texas

Fate, Texas

Harker Heights, Texas

Houston, Texas

Iredell, Texas

Kurten, Texas

Nevada, Texas

Richmond, Texas

Tyler, Texas

Kinnear, Wyoming

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Gardeners' Notes:


On May 22, 2011, jardinomane from Gatineau,
Canada wrote:

I live near Ottawa, in Canada (about USDA zone 4, I believe...) and I planted about 20 of those in a clump last fall. I planted them on the deep side, fearing they would get zapped by our really cold winters but I did not mulch. Guess what? They where among the most eager to poke through the still partially frozen ground. I am so looking forward to see them bloom! So, they are probably hardier than thought, given very well draining soil and a deeper planting.


On May 18, 2010, nutsaboutnature from Algonquin, IL (Zone 5a) wrote:

This is my first year with Gladiolus Byzantinus. I ordered them from Brent & Becky's & they were planted in October 2009.

I didn't even realize they were about to flower until a few popped open. The buds don't look like typical flower buds. They kind of remind me of "Wheat".

They're very, very pretty, kind of delicate-looking yet don't need to be staked. I've read that the flower colors can vary. Mine are a Deep Fuchsia & now that the first flowers have started blooming, the rest are opening quickly.

I love that they're not overpowering yet definitely hold their own in the garden. I will definitely be buying more.


On Jan 3, 2009, Lily_love from Central, AL (Zone 7b) wrote:

I received a handful of these byzantine glads. from a friend. I potted them up, they stayed dormant all through the growing season. I thought the tubers were gone, but recently I discovered they have sprouted indoor sharing a pot with my tender cannas. I'll add pix once these mature & flower this coming growing season.


On Nov 25, 2008, janecarol2 from Fort Jennings, OH wrote:

Bloom color can vary from deep purple red to dark hot pink. In my Ohio zone 5 garden it blooms late May/early June with yarrow and columbine. Soil can be average to dry. Beautiful.


On Apr 2, 2007, vossner from East Texas,
United States (Zone 8a) wrote:

Dainty and cheerful, does not need staking. Very special for me as received from a special friend.


On May 29, 2005, PurplePansies from Deal, NJ (Zone 7a) wrote:

Thhis plant as stated is "daintier" and more delicate than regular gladiolus..... the blossoms are smaller.... but still very showy..... the plants as a whole also look much better poking out of the ground...... they don't jut out at such strange (rigid) angles as regular gladiola.... looks much more "graceful" in the garden..... Very easy to grow.... overwintered perfectly without any real extra protection (mulch etc.) and no bulbs rotted.... planted a few and I believe every single one came up and has a flower on it.... I even think the buds before they open are pretty (resemble a green chasmanthe or some kind of grain)..... pretty strappy foliage..... bloomed for me in May/June :)
A real favorite! :)


On May 23, 2004, Dan_Brown from Elm Grove, LA wrote:

I find this heirloom plant very fulfilling and very common around NW Louisiana where I reside. I acquired my corms from old abandoned home sites and they have multiplied and bloomed faithfully every year without fail. After the blooms fade the bloom stalks are a tiny bit obvious, and the succession of opening allows for the lower ones to be dead before the top ones open, but the loveliness of the blossoms more than makes up for this distraction.
Blessed, Dan Brown, Elm Grove, LA


On Aug 16, 2001, Terry from Murfreesboro, TN (Zone 7a) wrote:

A more dainty plant than the modern cultivars, G. byzantinus is a very old plant that works well in cottage gardens. Its delicate blooms typically don't require staking.

Planted deeply (3-5") these bulbs can stay in the ground year-round in zones 5 and warmer. Give the bulbs well-drained soil to avoid rot, although they will tolerate a heavy soil as long as they aren't subjected to standing water.