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.

Can gladiolus be left 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.

Can I leave my gladiolus in the ground?

Dig gladiolus corms before the first hard freeze in autumn, but not until the foliage dies down after a light frost. Leave the corms in the ground as long as possible, as the green foliage absorbs sunlight, which provides energy and food to produce next year's blooms.