Growing and Saving Gladioli
Latin name Gladiolus, these members of the iris family are also known as sword lily. They are also sometimes referred to as "gladiolas."
Gladiolus are believed to have originated in South Africa, though some species are native to Europe and the Mediterranean. The first South African glads were taken to Europe between 1739 and 1745 by Dutch and English trade ships returning from India. The genus contains nearly 200 species and more than 30,000 cultivars. The name ‘gladiolus’ is derived from the diminutive form of ‘gladius,’ the Latin term for sword (‘little sword’).
- Cutting garden
- Landscape design
- Cottage garden
- Container garden
- Gladiolus are not started from seed, but rather from corms, which are modified underground stems that serve to store the plants' energy over winter.
- The earliest you can plant the corms is 2 weeks before your average last frost date, and you can succession plant them every 10 days for several weeks to encourage a longer bloom window.
- Corms should be planted 3 to 4 inches deep and the spacing may vary depending on your design, but should be between 3 and 6 inches apart. If you are growing in rows for cut flower production, you can plant the corms closer together (3-4 inches). If you are planting for landscape design, you can plant them 4 to 6 inches apart.
- When planting in landscape/garden beds/perennial beds consider clustering a minimum of 7 corms in one section to give a fuller appearance. Gladiolus are a bit like tulips in that they don't look as stunning when planted all by their lonesome!
- Provide full sun (they will tolerate a bit of shade) and regular watering (about 1 inch of water per week is sufficient).
- Provide a layer of mulch once the shoots have emerged to help discourage weeds and lock in soil moisture.
- Staking will help to keep the plants upright and with nice straight stems. For a few plants, simply stake individually with thin bamboo. For a larger planting, consider corralling the plants or using flower netting and stakes.
- Harvest when two blooms at the bottom of the plant have opened; this will allow the top blooms to open in the vase over time, making for a longer- lasting arrangement.
- Gladiolus are perennial in zones 7-10, and you can leave corms in the ground for care-free propagation. If you are in a cooler zone or you would like to move your glads, dig the corms in the fall and bring them indoors over winter to replant in spring.
- To save over winter, allow the plants to bloom then dig them up after the first fall frost, keeping the foliage intact. Place the entire plants in a dry, well- ventilated space to cure for a few weeks and allow the foliage to dry completely.
- Cut the stalks at 1 inch long and store corms in peat, shredded newspaper, or sawdust in a cool, dark, dry location (root cellar or basement is ideal; it must be a no-freeze location!).
- Ideal storage temperature is 40-50 F.
- Replant in spring.