After living in Colorado (usda2b) for 22 yrs, columbine are hardy plants, it's is Colorado state flower. The only ones I noted that would not come up regularly were a wild form whose flower stem grew only 3" tall, and had a 1" very pretty blue flower (nearly as blue as the "Suggest a Change" that's above the messages box. The normal garden type that I grew had tap roots going 6" deep and survived inches to feet of snow, and 2 nights a year of -18 degrees F. They had no mulch, just sandy soil, and never fertilized.
