threegardeners wrote: I'm in zone 5a and I've been leaving my glad bulbs in the ground for a few years now. It all began one year, while doing the fall chore of digging them all up, I noticed a zillion baby bulblets(?). Well, I wasn't about to dig THEM all up and find a place for them to overwinter. I left them in the ground and guess what? They came back the following year and have continued to do so, reaching blooming age and blooming beautifully. Now I leave my glads in the ground, just like any other perennial.
My soil is exceptionally sandy, which helps with drainage. These were not bought as "hardy glads" either.