Re: iris DIGEST V1 #954

Artic Fox is a oncer, being used  as control for Immotality.  Richard is
looking first at what sets flower bud.

 For regular oncers, the proceedure is a follows

1) plant reaches maturity
2) Temperature triggers flower bud set. For most cultivars, TBs that is, it
would seem to be 6 days
 with night time temperatures min between 16 and 21C. Plant waits in readyness
state for further development until
further conditions are met. Now the flowers are primmed, but not triggered.
3) Vernalization, cold period during winter
4) growth conditions in spring, warmth, moisture and warm enought to grow
5) Long night periods to act as photoperiod trigger.

For Direct, or summer rebloomers, they go directly from flower bud set to
bloom. No further trigggers needed.
Gowing directly from initial trigger to bloom , this seems to be about 3 weeks
in cold climate and proabably about 2 weeks
in warm climate.

For fall cyclic rebloomers, they sit and wait until nights are long enough to
trigger bloom. they don't need
vernalization.

'Whenever' rebloomers don't seem to need the warm period to have flower bud
set. They seem to set flower bud
 as soon as plant reaches maturity. Vernalization is carried forward in
increases by fast growth on the  increases bypassing
normal vernalization reset from apical dominance. Thus if the increases grow
too slow in spring, they will have vernaliation state reset,
and will not be able to "whenever" rebloom

Chuck Chapman

Date: Mon, 09 Nov 2009 16:27:05 -0500
From: autmirislvr@aol.com
Subject: Re: [iris] iris DIGEST V1 #953

Chuck, Just so I understand what I'm supposed to understand--

It's my understanding that bloom is set after spring bloom,  then stalks are
"initiated" later, when the conditions are right?  Whatever the process that
causes "initiation" would depend on temperature and/or other conditions like
soil composition & moisture?  Soil composition & moisture being two key
components in rhizome growth?


<<hot at nifght to get flower bud
et temperature,>>

Do you have an estimation on the average time elapse between "initiation" and
open bloom?  It would vary depending on temperatures?  Just as spring stalks
do?

My goal is to heavily incorporate irises that bloom here in the summer in
hopes of creating more irises that bloom well in advance of our fall frosts.
I've already incorporated a number of "sporadic" rebloomers.  I am getting
things that rebloom, sometimes in the first generation.  It's always a
thrill.

Betty Wilkerson
Bridge In Time Irises
KY Zone 6








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