I had colchicum flowering well when I lived about 100 miles west in Oklahoma, but here in Arkansas, they flourish vegetatively but seldom rebloom.

I have some wild species colchicum sent to me from Hungary that do flower, though fairly sparsely.

For instance, a named cultivar bloomed the first year, but now four or five years later has expanded into a foot wide clump, but has never flowered since the first year. I just get a very nice cluster of leaves ;)

My soil might be a bit wetter in summer than Oklahoma, but not much. The soil here is more clay than the silty clay that I had in Oklahoma.

What am I doing wrong for these guys?