Winter care of gladiolus
Gladiolus are hardy in zone 7 and up and can be left in the ground year round. In areas with deep frost, zone 6 or lower, they need to be lifted from the soil and stored for the winter. Dig up the corms before the first frost or when the tops die back. Remove browning foliage and trim it to 1/2 inch of the corm. Shake off the soil and let the remaining stubs dry for 1-2 weeks in a warm, ventilated area. Once cured, remove dried stubs, discard old corms and cormels (optional).
To prevent rot, dust the large new corms with a fungicide. Store the corms in a ventilated container such as paper/plastic mesh or cloth bag in a dark, dry, frost free place at 35-45 degrees. Cormels can also be stored and planted the following spring.
You can also drop a mothball in each bag of gladiolus to deter mice and kill overwintering thrips.
Soak the corms in hot water (160F) for 2-3 minutes and allow them to dry before storing. Or you can dust them with Carbaryl
Soak the corms for 6 hrs in a solution of 4 tsp. of Lysol to 1 gal of water before planting.