Expert: Long Island Gardener - 9/12/2008

Question
This is my first year growing gladiolias.  I need to know when to cut off the stalks and remove the bulbs.  Before or after a frost and also how to store them for the winter.  Thanks

Answer
Gladiolus stay in the ground until the first hard frost.  Although some industry professionals insist they can be dug 1 to 2 months after flowering, most agree that post-flowering 'curing' is key to future bulb health and they should be left in the ground as long as possible after flowering has finished.  That means keeping them in the ground until foliage has died down on its own.

Dig Corms with a fork, not a shovel, so that you can remove some Soil around the Corm and minimize injury from handling.  Dust off the Soil, and dispose of diseased or suspicious-looking Corms.  You can cut the stem 2 inches above the Corm at this point, and leave them out to dry.  To save small 'Cormlets', which can be planted and will bloom in 2 or 3 years, leave the Corms out to dry for up to 3 weeks.  Ambient room temperature should be as high as 85 degrees.  Then one by one, break the Cormlets off the old Mother Corm, and store through Winter.  The original Mother Corm should be discarded at this point.

Store in a cardboard box or mesh bag with low humidity and near-freezing temperatures.

University of Minnesota posts a page on Gladiolus that you might find helpful:

www.extension.umn.edu/distribution/horticulture/DG1154.html

Thanks for writing.

THE LONG ISLAND GARDENER