Known for its huge, showy blooms and long flower spikes, gladiolus is a classic perennial. Gladioli are a wonderful choice for summer bouquets because they are excellent for cutting. Here’s how to grow gladioli in your own backyard or flowerbed.
For years, these traditional flower spikes have adorned summer gardens and bouquets. You can find a gladiolus to suit your personal style among the many varieties available to gardeners today. Gladiolus are typically divided into groups based on the size of their flowers, which range from microscopic to enormous.
They come in a wide spectrum of hues, from garnet red to hot pink to yellow to cream to coral to even green. USDA zone 7 is the only place where most gladiolus types can survive the winter. A hardy gladiolus is one exception (Gladiolus nanus). On corms that are hardy to USDA zone 5, you’ll find 20-inch-tall gladiolus plants.
Gladiolus are popular cut flower plants, but they also look great in an annual garden with zinnias, lavatera, and celosia.
The Gladiolus
Known as “glads,” these attractive flowering plants come in a wide range of colors and can grow to a height of 2 to 5 feet. In terms of size, their blooms range from “miniature” flowers less than 3 inches in diameter to “giant” blossoms more than 5 inches in diameter!
Staked taller plants in the back of the garden to provide height contrast with lesser ones.
In USDA Hardiness Zones 8 and higher, gladiolus plants can withstand the winter cold. When growing gladioli in Zones 7 and lower, corms should be dug up, saved, and replanted in the spring of the following year. Find your zone here and follow the guidelines below to get started.
Planting
Once the risk of frost has passed and the soil has warmed to at least 55°F (13°C), gladiolus corms can be planted in the spring. Check the dates of your local frost here.
Plant a new set of corms about every 10 days from the end of the frost date to the beginning of the summer. As a result, flowers will continue to appear until the beginning of the fall!
Glads can take anywhere from 60 to 90 days to root, grow, and bloom, depending on the type.
Choosing and Preparing a Site for Planting
Plant glads in full light for the most beautiful flowers.
Gladioli prefer fertile but not overly rich soil. They can’t survive in damp, heavy soil.
The first step in preparing your garden is to loosen the soil around 12 to 15 inches deep with a garden fork or tiller. Compost or aged manure should be incorporated into the soil after it has been loosened by a 2- to 4-inch layer.
Planting Gladiolus: A Quick Guide
- The bigger the circumference of the corm, the larger the blooms will be.
- Place the pointed end of the corm into the hole, about 4 inches deep. Using a shovel, firmly press the earth into place.
- Leave a 6- to 8-inch space between each corm.
- Plant gladioli in rows if you intend to use them as cut flowers. Maintaining the plants and gathering the blooms is a lot simpler when you have a helper.
- Plant the corms in groups of seven or more in borders or annual beds for the maximum impact.
- The corms should be well-watered before planting.
- The stakes should be erected at the time of planting if you’re planting tall cultivars. Keep an eye out for tangled roots and avoid using sharp stakes.
Care & Planting
South African Gladiolus thrive in a sunny location with sandy loam soil that drains well. Gladiolus will thrive in any soil that is suitable for growing vegetables. Adding compost to your garden beds in the spring will aid with water drainage and provide nutrients for your plants. To get the finest results from your gladiolus plants, keep the area surrounding them free of competing plants and weeds.
Two weeks before the last projected spring frost, gladiolus can be planted. Planting and blossoming will take between 70 and 90 days. As soon as spring arrives, start a new batch of flower corms and repeat the process until early summer to ensure a steady supply of blooms. In order to get the best results, plant the corms about 2 to 6 inches deep and cover them with 2 inches of dirt. Rows of 10 to 15 corms should be spaced 5 inches apart. Hill up the soil around the plant’s base once it reaches a height of 6 inches or so to provide support for the stem.
When the plants are between 6 and 10 inches tall, use a water-soluble fertilizer at a distance of 4 to 6 inches from the stems. When the flower spikes begin to turn color, apply a second application. Remove all weeds and mulch the plants with 2 to 4 inches thick bark mulch, wood shavings, or straw to keep the soil free of weed seeds. To get the most blooms, make sure your plants are well-watered.
Staking is likely to be necessary on taller kinds in order to keep the flower spikes from blowing over. Individual spikes can be staked, or a grid made of stakes and string can be used to maintain flower stalks upright. Single-stem supports are the best option.
A Guide to Growing Gladiolus
A 2- to 4-inch layer of mulch around your gladioli can help retain moisture and keep weeds at bay.
Your plants need to be watered often during the summer if you get less than 1 inch of rain a week. Moderate irrigation, while they’re growing, will keep the soil moist.
In order to maintain a steady supply of blooms, remove any faded or dead flowers. At around 2 to 3 inches above the soil, cut off a flower stem when all the blossoms are gone.
Remember to let the plant alone so that it can mature and produce more corms for the following season.
Protection for Gladiolus in the Winter
Put down a layer of hay or straw if you live in USDA Hardiness Zone 8. Gladiolus may survive the winter in milder climates if a harsh freeze (28°F or lower) is not regular.
In colder places (Zone 7 or colder), pull up gladioli corms once the foliage has faded following the first fall frost. A light frost will harm the leaf, but not the remainder of the plant. Be sure to dig up the gladiolus corms before a heavy winter, or the plants could be fatally harmed.
See corm storing advice below.
Pests/Diseases
- Rotting gladiolus stems (Fusarium wilt)
- Mold that is gray in color
- Viruses
- a yellow aster
- Spider mites
- Thrips
- Aphids
Types of Plants to Consider
- Because of its stunning deep pink blooms, ‘Candyman
- The flower spike of ‘Dream’s End,’ which can reach a height of three feet, makes it an excellent rear border plant (and it has pretty light orange flowers with large yellow centers)
- Pink-tinged white blossoms adorn the stems of the perennial ‘Prins Claus.’
- Dark purple-red blossoms and a height of 36-60 inches characterize the flower variety ‘Black Star.’
- Insect-resistant and able to bloom in full sun or partial shade, Glamini Glads are ideal for the garden. Their lesser height makes them ideal for flower beds in the middle or at the front.
Storage of the Crops
When the lowest flowers on the stem begin to show color, cut flower spikes on a slant if you’re growing gladiolus for bouquets. Leave as least four leaves on the plant while pruning the flower stem to feed the corm for next year’s flowers. When cutting a flower stem, immediately submerge the cut end in water. For harvesting gladiolus, our galvanized, four-section Flower Caddy is the best option.
To Make Bouquets of Gladiolus Flowers,
Avoid cutting the flower stalks in the heat of the day by cutting them early in the morning or late at night.
Bring a bucket of lukewarm water and a sharp knife to the flower bed.
Trim off any flower stalks that have more than one or two open petals. After you’ve placed them in a vase, the remaining buds will begin to open.
To insert the stalks in the bucket, cut them in half diagonally.
If you wish to replant the corms, make sure they have at least four leaves before doing so.
Before placing the flowers in a vase, put the bucket of flowers in a cool, dark spot for a few hours.
Each flower stalk should be clipped approximately an inch from the bottom every few days to remove the lower fading blossoms.
Gladioli Corm Digging and Storage
Dig up gladioli corms after the first fall frost in colder places (Zone 7 or colder). The leaves will be killed by a light cold, but the remainder of the plant will not. Be sure to dig out the gladiolus corms before a hard freeze (28°F), otherwise, the plants could be fatally harmed.
Use a spade and dig up the entire plant, gripping the top to pull it out of the earth. Avoid bruising or damaging corms while digging. Discard any damaged corms and shake off any loose soil. Trim the corm’s stalk to a height of 1-2 inches above ground level. If you like, you can store the little cormels separately. If you replant them every spring, they’ll blossom in two to three years.
If the weather permits, let the corms air dry for one or two days in the sun. Corms should be placed in flats or trays made of wood after removing any surplus dirt. Cure for two weeks at a temperature of 80-85°F (27-29°C) in a well-ventilated environment. Removing and discarding the oldest corms (from the base of the new one).
The corms’ husks should not be removed.
To prevent illness, use a fungicide on the corms (also known as “bulb dust”). Shake the dust and bulbs vigorously in a paper bag.
Paper or canvas bags, pantyhose, or old onion sacks can be used to store the corms. Distribute the containers in a way that allows for the free exchange of oxygen. In a low-humidity environment, keep the corms around 35 to 45°F (2 to 7°C). Basements are a good option. Corms should not be allowed to freeze.
Beautiful blooms will follow this year’s replanting of these corms in the spring.
Wisdom and Humor
In August, the gladiolus is one of the birth flowers.
Sword lilies, or gladioli, are often referred to as such because of their blade-like leaves. “gladiolus” is derived from the Latin word “gladius,” which means “sword.”
Gladiolus is a flower that represents remembrance in the language of flowers.
