Gladiolus (glad-ee-OH-lus), also known as “glads,” is a perennial cormous flowering plant belonging to the genus Gladiolus and family Iridaceae, commonly known as the Iris family.
The genus name Gladiolus comes from the Latin word “gladius,” which means sword. Therefore, the name literally translates as the little sword. It also references the plant’s sword-like shape of leaves.
Gladiolus was also previously called Xiphium, which was derived from the Greek word “xiphios,” meaning sword.
This herbaceous perennial is native to the Cape Province of South Africa but can also be found in Northwestern and Eastern Africa, Mediterranean Europe, Madagascar, Arabian Peninsula, and Asia.
Gladiolus is prized for its brightly-colored trumpet-shaped flowers and green, sword-shaped leaves.
This flowering plant is also known by several common names, including:
- Common Gladiolus
- Garden glad
- Gladioli (plural name)
- Flag flower
- Sword lily
Gladiolus are commonly grown and widely cultivated as a garden ornamental and cut flower.
The genus also has over 200 recognized species, and among them include:
- Gladiolus abyssinicus
- Gladiolus alatus
- Gladiolus communis
- Gladiolus dichrous
- Gladiolus equitans
- Gladiolus floribundus
- Gladiolus grandiflorus
- Gladiolus italicus
- Gladiolus murielae
- Gladiolus palustris
Gladiolus also comes in various sizes, with the three most popular hybrid groups, namely:
- Grandiflora Hybrids
- Dwarf Grandiflora Hybrids
- Gladiolus Nanus Hybrids
Some notable gladiolus varieties include:
- Black Star – deep purple-red blooms
- Costa – Ruffled, blue-purple flowers
- Fun Time – ruffled, yellow flowers with bold red edges
- Green Time – lime-green flowers
- Lumiere – mauve, hot pink, and violet flowers
- Priscilla – creamy-white flowers with yellow centers and pink edges.
- Vulcano – fuchsia-pink flowers
In addition, Gladiolus is also often associated as a symbol of the following:
- Healing
- Honor
- Intelligence
- Strength
- Victory
- Moral Character
Quick Facts On Gladiolus
- Family: Iridaceae
- Light: Full sun; Partial Shade
- Temperature: 50° to 70° degrees Fahrenheit
- Water: Moderate watering; Moist, well-drained soil
- Fertilizer: Balanced Liquid Fertilizer
- Propagation: Seeds or Corms
- Common Problems: Leaf spot, Rust, Corm Rot, and Thrips
Gladiolus Care
How Big Does Gladiolus Grow?
Gladiolus is a fast-growing flowering plant, typically reaching 2′ to 5′ feet tall.
The dwarf gladiolus hybrids grow 20″ – 25″ inches tall, while giant hybrids can even reach up to 8′ feet.
When Does Gladiolus Flower? Are The Flowers Fragrant?
Gladiolus is distinguished by its noteworthy features, such as its gorgeous spiked flower inflorescence with brightly colored funnel or trumpet-shaped petals commonly positioned on only one side of the slender stem.
The flowers open in succession, starting from the bottom up to the top, with the biggest flower at the plant’s base.
Miniature or dwarf gladiolus flowers blossom in less than 3″ inches in diameter, while giant flowers spread more than 5″ inches across.
Gladiolus blooms come in a variety of colors, ranging from the following:
- Cream
- Off-white
- Tan
- Gold or Yellow
- Green
- Orange
- Pink or Hot pink
- Purple or Lavender
- Blue
- Red or Burgundy
The foliage of Gladiolus are green, sword-shaped leaves in upright fans, often reaching less than 6″ inches long and 1″ to 3″ inches wide.
In general, Gladiolus will bloom from late summer to frost or early fall with an attractive scent reminiscent of roses.
However, the blooming season may also vary depending on the different hybrids.
For example, Gladiolus Nanus Hybrids usually bloom in early summer and open with 3 to five flowers.
In comparison, the Primulinus Hybrid group will begin to flower during the midsummer and may produce up to 20 flowers.
In addition, the Grandiflorus Hybrid group begins blooming from late spring until fall, blossoming up to 12 flowers at the same time.
What Are The Lighting Needs And Temperature Requirements?
Gladiolus thrives in full sun with at least five hours of full sun each day, and you can rest assured its blooms will be vivid.
But this flowering plant may also grow and flower in partial shade, though its flowers will not be as brightly-colored and won’t grow quite well.
The ideal temperature for Gladiolus ranges between 50° and 77° degrees Fahrenheit to produce the finest growth.
In addition, Gladiolus is winter hardy in USDA Hardiness Zones 7 to 10, meaning its corms can be left year-round in the ground in those areas.
How And When To Water And Fertilize Gladiolus?
Gladiolus need regular watering and moisture during the active growing season, especially during dry spells and summer.
You must also ensure at least an inch of water every week to keep the water moist, as Gladiolus tends to become more prone to disease and pests when it gets stressed by drought and heat.
Lack of water may also cause smaller florets, shorter spikes, and smaller corms.
After the blooming period, you may reduce watering. Although, you may also apply 2″ to 3″ inches of mulch to retain ideal moisture levels.
For the fertilizer, feed your Gladiolus with a water-soluble fertilizer or balanced liquid fertilizer when it’s already 6″ to 10″ inches tall.
Apply the fertilizer 4″ to 6″ inches away from the plant’s stems.
What Is The Best Soil For Gladiolus, And When Should You Transplant?
Gladiolus is an easy-to-grow and adaptable flowering plant. It grows best in humusy, fertile, well-drained soil with a constant moisture level.
Gladiolus may also grow in any soil, as it’s not as fussy, but it won’t do well in clay and heavy, soggy soil.
If your soil isn’t in its ideal conditions, you may mix compost like hummus to improve its fertility and consistency.
It’s best to transplant your Gladiolus after its blooming period and when it’s starting to die back in the fall.
For planting corms, it’s best to do it from early summer to early summer.
Here’s how to plant your Gladiolus corms:
- First, prepare the soil by loosening it to 6″ to 10″ inches deep.
- Then, add an all-purpose granular fertilizer and compost or manure to encourage the plant’s full growth potential.
- Next, plant the large corms 6″ to 8″ inches deep, while the dwarf gladiolus corms are 4″ to 6″ inches deep with the pointed end facing up.
- Ensure the corms are spaced 4″ to 6″ inches apart.
- Finally, water the corms regularly until you see a sprout.
Does Gladiolus Need Special Grooming Or Maintenance?
Gladiolus doesn’t require regular grooming and maintenance, such as pruning and deadheading, but you may pinch back the dead or faded flowers to ensure continuous blooms after they wither.
You may also deadhead the flower stalks, cutting the stem off above 2″ to 3″ inches above the soil.
It’s also good to support Gladiolus, especially those that grow 3′ to 4′ feet or taller.
Do this by putting stakes at the ends, tying the stems to bamboo canes, or surrounding the stalks with twine to prevent them from breaking, bending, and being toppled by a heavy downpour or gusty wind.
How To Propagate Gladioli?
Gladioli can be propagated via the following methods:
- Germinating seeds
- Dividing Corms
Gladiolus seed pods appear after the flowers are spent, and the petals have fallen.
For germinating seeds, do the following steps:
- Wait until the gladioli seed pods are dry and turn brown before harvesting seeds.
- Crack the seed pods open over a bowl or any container to catch the seeds.
- Place the harvested seeds in an envelope and put them in a dark, cool location until spring.
- In the late winter, sow the seed in trays or flats indoors.
- Sprinkle fine sand over the tops of the seeds, covering them but not totally.
- Keep the seeds in a moderately moist and warm location.
Seedlings will start to appear in 4 to 5 weeks.
For dividing corms, here’s how to do it properly:
- Dig the gladioli corms in the fall using a spade. Usually, it’s 4 to 6 weeks after the blooms.
- Shake off excess soil from the corms and brush the dirt off using your hand. You may also wash the corms if they are dingy.
- Cut the top of the gladioli 1″ to 2″ inches above the corm.
- Dry the corms in the sun for 1 to 2 days.
- Cure the corms for 2 weeks at 80° to 95° degrees Fahrenheit before breaking the cormlets.
- Remove the oldest corms (from the base of the new corms).
- Dip each gladioli corm in fungicide to avoid the transmission of diseases.
- Store the dusted corms in cloth bags or paper bags at 35° to 45° degrees Fahrenheit in low humidity.
Sword Lily Pests And Disease Problems
Sword lilies are susceptible to diseases, including:
- Aster yellows
- Botrytis
- Crown rot
- Gladiolus corm rot (Fusarium wilt)
- Mosaic virus
Keep a lookout for the following pests, namely:
- Aphids
- Mealy bugs
- Spider mites
- Thrips
If you ever notice any sign of infestation, it’s best to treat the infected plants with insecticide or insect soap.
Uses Of Sword Lily
Sword lilies are striking flowering plants, making them excellent garden ornamentals for flowerbeds.
Their brightly-colored flowers add a pop of beautiful range of colors to the landscapes, gardens, decks, patios, and borders.
The flowers of the Sword lilies are also often used and widely cultivated as cut flowers, making them a great choice in flower arrangements and bouquets.