What month do you plant gladiolus bulbs?
Emily Wilson
Updated on March 03, 2026
What month do you plant gladiolus bulbs?
spring
Planting: Plant gladiolus corms in spring 2 weeks before your last expected frost date. To enjoy flowers all summer, plant your Glads every 2 weeks until early July. This will stagger the plantings and flowering times. You can also extend the flower season by growing early, mid and late-season Gladiolus varieties.
Do gladiolus come back year after year?
Gladioli grow from corms, which are underground storage organs much like bulbs. Gladiolus come in a riot of colors and will re-bloom every year. Northern gardeners will need to lift the corms in fall and store them through the cold season to protect the gladiolus from freezing temperatures.
How long does it take for gladiolus to grow from seed?
Keep the medium moderately moist in a warm, bright location. Seedlings will emerge in 4 to 5 weeks. Allow seedlings to develop a few true leaves before hardening them off.
What should I plant in front of gladiolus?
Some good flowering companion plants for gladiolus include zinnias and dahlias. Gladiolus plants like sun and well drained, sandy soil, and plants that grow well with gladiolus need the same kind of soil conditions. Really, basically any plants sharing the same requirements will work.
How many gladiolus bulbs are in a hole?
Plant corms 2 to 6 inches deep, depending on their size, and cover with 2 inches of soil. Space corms 5 inches apart in rows or groups of 10 to 15 corms. Once the plants are about 6 inches high, hill up the soil around the base of the plant to help support the stem.
How many years do gladiolus bulbs last?
Gladioli provide a long season of floral interest both outdoors and indoors. They generally bloom for two months, but this varies depending on the hybrid. There are ways to extend their season both outdoors and indoors.
Will gladiolus bulbs multiply?
Like many perennial plants, gladiolus grows from a large bulb each year, then dies back and regrows the following year. This “bulb” is known as a corm, and the plant grows a new one right on top of the old one each year.
Can I leave gladiolus in the ground over winter?
In warmer regions, gladiolus can remain in the ground through winter, provided a hard freeze (28°F or colder) isn’t common in your area. In colder regions (Zone 7 or colder), dig up gladioli corms once the foliage has faded after the first fall frost. A light frost will kill the foliage, but not the rest of plant.
Should you soak gladiolus bulbs before planting?
Gladiolus grows from underground, bulb-like structures referred to as corms. In his book “Growing Flowers for Profit,”, Craig Wallin recommends soaking the corms in plain tap water a day before planting.
Can gladioli bulbs be left in the ground?
Gladioli can be planted directly in the ground in May – they can be planted a couple of weeks before the last expected frost, usually early May depending on where you live.
Do gladiolus flower more than once?
Although they will not flower more than once in a season, home gardeners can stagger plantings for continuous bloom in the gladiolus bed throughout the summer. Gladioli grow in USDA hardiness zones 7 to 10, according to Missouri Botanical Garden.
How late can I plant gladiolus?
Plant gladiolus anytime between early May to the middle of June, advises Ronald C. Smith of North Dakota State University Extension. Plant larger corms at a depth of 6 inches, and space them 6 inches apart.