The later bloom is often a by-product of an unusual weather pattern.
We occasionally experience a later bloom (after regular bloom season)
and it occurs on a rhizome that matures later than the rest. This
happens with 'periodic' bloomers. As the rhizomes mature, they bloom.
So there are more rebloom patterns than just fall rebloomers. Right
now we also have a bloom opening in the base of a fan. My thoughts
are, if it isn't able to create enough fans to survive, it shouldn't be
on the market. There are so many outstanding iris available today
compared to what we started with ever so long ago.
Hope this helps. Maybe someone else has a better explanation.
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