Monday, August 20, 2012

Where's the Rebloom when it's Hot and Dry?

By Betty Wilkerson
South Central Kentucky, Zone 6

It’s not news to our readers that 2012 has been an unkind year, weather wise, in much of the United States.  Extremely high temperatures and drought conditions inhibit most rebloom of tall bearded irises.  Yet, ‘Immortality’ and my seedling number 1810-15Re opened blooms in early August.  They are both growing at the end of one of the new beds (2010) and get a touch of late afternoon shade.

My primary hybridizing goal has always been to create irises that will rebloom in my zone 6 garden.  My current breeding strategy has been to cross award winning spring-only irises with great form and patterns in combination with well formed rebloomers and rebloomers with strong rebloom.  Only the strongest rebloomers have a chance of producing rebloom children in this difficult area.  

‘Immortality’
 is a reblooming staple.  Even so, it doesn’t always rebloom here.  It really wants everything just right.  Last year suited its temperament: it bloomed a lot during the summer and fall in the new beds.
'Immortality' (Zurbrigg 1982)
1810-15Re (Wilkerson Seedling) 

1810-15Re is one of the seedlings from my “kitchen sink” cross.  The pod parent, a near-white over dark blue/purple is 1605-01:9415RE (((Victoria Falls x Vanity) x Immortality) x (Love Lines))) x (Feedback x Champagne Elegance).  It contains several quality spring blooming irises mixed with good rebloomers. During a move to Allen County, I lost the pod parent, a near amoena seedling with white standards and dark blue purple falls.

A sibling, 1605-02Re, is white over lavender and reblooms in the fall in my zone 6 garden.  Dr. Raymond Smith’s rebloomer, ‘Light Rebuff,’ a very pale, translucent pink, is the pollen parent.

1605-02Re (Wilkerson Seedling) 
Only three seedlings sprouted the first spring of this cross, and two put up stalks that first fall.  They were given the numbers 1810-01Re & 1810-02Re.
1810-01Re (Wilkerson Seedling)  
1810-02Re (Wilkerson Seedling)  

Another thirty eight sprouted the second spring.  Twenty two from this cross bloomed off season over the next three or four years.  Others were used in breeding, but did not rebloom.  This is an assortment of seedlings from this cross. Both #6 & #10 put up late stalks in 2006.  1810-01Re and 1810-15Re are the top rebloomers, with 1810-15Re being the best.

1810-06 (Wilkerson seedling) 
1810-10 (Wilkerson Seedling) 
1810-03Re (Wilkerson Seedling) 
 1810-07 (Wilkerson seedling)
1810-08 (Wilkerson seedling) 
1810-14Re (Wilkerson Seedling)  
These are definitely not the end product, but a step on the path to better rebloom.  Some crosses using this group of seedlings have been very interesting.  My favorite results were from a kitchen sink child crossed onto ‘Enjoy the Party.’  It has given some very nice ringed bi-tone seedlings with fall rings.  One has even fall bloomed!  Not enough, and not often enough, but a step in the right direction. 

Producing reblooming irises is a time-consuming passion, but the rewards are great:  a period of longer bloom for our favorite flower.  Let me know if you enjoyed this peek into a rebloom cross.