Hello, Having a gladiolus overwinter is not a matter of planting it deeper in the soil (yes, in principle if you go below the frost line the soil does not freeze) profile, but knowing the wintertime soil temperatures in the bed remain above freezing. Areas on the west side of the home say between a basement wall and a sidewalk or driveway may remain above freezing to allow the bulb to survive, but the bulb cannot be planted at a level below what a typical planting would be. Since gladiolus bulbs are considered a summer bulb, you may have difficulty finding them in the fall, but if you do, you could plant them in the fall. Purchasing them via mail order is an alternative. I suggest starting our with a few bulbs of a specific variety and see how it goes before proceeding in a big way
