Answer: Glads are hardy in zones 8-11. They are sometimes hardy in zones 6-7 (you are in zone 6), if they are covered with a thick mulch or in ground next to the house where warmth comes through the foundation. To be on the safe side, I'd dig them, but you can also try leaving a few to see what happens.
Glads are dug for storage 4-6 weeks after the last flowers fade.
1. Shake as much soil as possible off and then trim the leaves back to about one inch.
2. Allow the corms to dry for a week and then gently brush off any more soil.
3. Store them dry in a mesh bag (like onions come in) or old panty hose in a dark, cool (35-41 degrees F) spot. Make sure its rodent-proof as mice love these tasty corms!
Plant next spring after the last frost, usually around April. One tip - try not to plant Gladioli in the same spot for several years in a row. Using a new location every year helps to assure a healthy and vigorous crop.
Assuming you are referring to tuberous begonias, dig and store them as you would glads. They should also be planted outside when the last frost is over in spring.
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