Easy to grow gladiolus


Q. Are gladiolus easy to grow here? How can I find some?

Theresa from Youngstown

A. Yes. Glads, as they are often called, are easy to grow, but storing them can be a pain because they are a tender bulb.

Gladiolus is another old-fashioned summer flower, a native of South America.

Glads are a member of the iris family, they are diverse in color, flower size, height, and shape. Glads bloom from July until frost. Staggering planting times will give you up to three months of color. They do not like heavy clay, but prefer sandy loam. So, adding organic matter greatly improves drainage. A soil pH of 6.0-6.5 is preferred. It is recommended the soil be worked two weeks before planting.

They require full sun, good aeration and may require staking. As with all bulbs or corms, the larger the bulb or corm, the larger the plant and flowers. Days to bloom vary from 60 to 120 days, so check the package.

Gladiolus grow from corms, different than bulbs. Bulbs have layers of tissues, corms are a solid mass of tissue, actually compact stems. Glads are not hardy here, so they need to be dug up about six weeks after blooming, then dried and stored. The leaves should be yellowed or dying. If stalks still look healthy, leave them in the ground until just before the first hard freeze.

Gladiolus are susceptible to some disease issues late in the season. I sprinkle the corms with a fungicide before planting to prevent fungal diseases. Another problem can be thrips. They attack the foliage and flowers. They leave whitish streaks on the leaves, if florets are attacked, they will be discolored and misshaped.

To store corms, carefully lift the corms from the soil, shake off excess dirt, and cut the leaves back to the corm. Place them in a well-ventilated, light, and warm place to cure for a few weeks. Once they have cured, separate any new corms from the original, remove loose husks, place in paper bag for winter storage. Label the bags. Store in a dark, cool, dry, well-ventilated place. Ideal storage temps are from 35-45 degrees. For information, go to go.osu.edu/glads.

Marilyn McKinley, an OSU Extension master gardener volunteer in Mahoning County, provided today’s answer. Call 330-533-5538 to submit your questions. Regular clinic hours are 9 a.m. to noon Mondays and Thursdays.