Winterizing your Summer-Flowering Bulbs
Many summer-flowering bulbs, such as Dahlia and Gladiolus, are not winter hardy. Instead, they should be winterized and re-planted the following spring.
Step 1: Dig up your Dahlia and Gladiolus bulbs after the first frost.
Step 2: Cut the stems off the bulbs
Step 3: Store them in a dry, cool and dark location during the winter.