Re: HYB: Daylength independent


Betty, your post gave me another thought.

What if some of these 'summer' bloomers actually <are> responding to daylength, but maybe not the same way that fall bloomers do. Suppose they respond to the shortening days that start at the summer solstice? June 22. And in our warmer climate, are able to develop stalks fast enough to bloom in July.

If IMM (and the others you mention) can quickly respond to the slightest shortening of days, plus have less stringent cool temperature thresholds, maybe that explains why it acts like a daylength independent bloomer here, but not farther north, where (I assume) temperatures are cooler & growth slower?

& maybe the others have a range of threshold temperatures (cumulative or single event?)

I wish IMM weren't so fussy about being moved - I'd put some in a pot and do some experiments.

I don't have records on bloom timing of SDBs etc, but TBs start here around mid April (if they haven't been frozen out), peak the first week of May, and generally are finished by late May, tho I have seen a stalk or two still blooming in early June. IMM sends up stalks throughout that time.

Betty, what's the earliest <after> spring TBs finish blooming that you've seen a stalk?

Mike Sutton, what about the 'CA' rebloomers? Maybe they are missing the cool temperature threshold entirely or it's a higher threshold. How soon after spring TBs finish do you start seeing rebloom?
--
Linda Mann east Tennessee USA zone 7/8
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