Re: Florida suggestions & bloom triggers

Rick Tasco wrote:
> I think the problem with bearded iris in your area is
> not enough cold, especially the night temps.  If you would get some
> nights in the 30's then you may have chance.     

I am still intrigued by the differences in bloom initiation among so
many cultivars. What Rick says seems to apply to oncers based on posts
to the list (all I know about irises <grin>).  

But what about rebloomers that set their buds in the summer?  After
reading posts on and off list this fall about timing of fall rebloom in
some cultivars compared with timing of rebloom here in my "garden", I
suspect there is also a cold temperature trigger in addition to
decreasing daylength that triggers the start of fall growth of bud
stalks.  In my frost pocket, it got unusually cold here late in the
summer for a brief period - cold enough to trigger bud formation in my
Christmas cactuses on the window sill, which I think requires
temperatures in the 40s for several days?  This may have triggered my
fall reblooming irises (QUEEN DOROTHY, HARVEST OF MEMORIES) to bloom
about a month earlier than those belonging to other folks in Tennessee
and Mississippi.

So maybe a cold weather ever-bloomer like IMMORTALITY or other
ever-bloomers from warm climates (California) don't have this cold
temperature trigger (assuming my observation has anything to do with
what is really happening).  Or the trigger is not as low a temperature
as the fall bloomers.  What are the summer soil/air temperatures in
areas where those California ever-bloomers bloom?  Here, IMMORTALITY
sets buds all summer, with high temperatures at least in the upper 90s. 
Night-time summer air temperatures stay in the lower 70s most of the
time, but occasionally dip into the 60s.

Does anybody know when buds are set in fall bloomers and what triggers
that bud formation?  And when does spring flower bud formation in those
repeat bloomers happen?  And what triggers it?  Is it the same trigger
in fall and spring?  Are they setting buds in the fall for spring bloom
or were those set the preceding spring?

If I remember, I will stick a pot of HARVEST OF MEMORY in the fridge for
a week next summer after the summer solstice and see if I can trick it
into blooming.

Does anybody know if there is any indication that any plants initiate
bloom in response to cumulative decreasing temperatures?  

Linda Mann east Tennessee USA
Full of questions this morning - been studyin' on this a while...
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