Growing Irises Out East: Sharing Stories of Rebloom

by Heather Haley

In addition to being a member of the American Iris Society (AIS), I am an active participant and volunteer in North Carolina Cooperative Extension programs. I completed the NC Farm School program 2019. Earlier this month, my husband Chris and I hosted a farm visit for another Farm School graduate, her instructor, and a new horticulture extension agent in our county. 

Heather's family with reblooming iris 'Mesmerizer' on their farm in Ramseur, North Carolina
photo by Grace Kanoy, GeoCore Creative Inc.

Winter is approaching quickly, and Chris and I spent that morning straightening up the kitchen -- just in case we needed to move farm conversations inside. When the visitors arrived, they were met with spring-like conditions and all enthusiastically wanted to visit the production field for bearded irises. The intent of this visit was to support a beginning nursery owner, discuss interests, and share experiences in the business of horticulture. However, once visitors realized the farm had several irises blooming in mid-November, they lost all thought of business pursuits and became highly inquisitive about these plants. 

One inquired, "Are the irises CONFUSED?" I laughed gently and replied, "No. Those are rebloomers. They are just doing what they do best."

Chris and I explained that each of the various irises on our property has genetic information coded in their DNA. Differences in DNA make each iris interesting and different from other varieties. Some iris genes control traits like flower color, whereas others can modify growth and reproductive cycles. With the right DNA sequence, an iris can shorten or skip summer dormancy and proceed directly into its next growth cycle. If climate and cultural conditions are just right, it is possible for daughter rhizomes to bloom in the same year as their mother. These irises aren't confused; they are just unusually prolific. Science buffs use the term "remontant" to describe plants that flower more than once in a growing season. "Rebloom" is the colloquial term for this phenomenon, and an entire chapter on it appears in the third AIS study of the genus Iris: a 1978 book titled The World Of Irises*. 

*The World of Irises book is now out of print, but used copies can be found online. Wayne Messer and Bob Pries have also transcribed select book chapters (including Raymond Smith's chapter on Rebloom) for Iris Encyclopedia. AIS is always looking for volunteers who can type existing content into this online library. If you are interested and available for transcription projects like this, please reach out to Bob at bobpries3@gmail.com. 

Chris reminisced about our household's earliest experience with a reblooming iris. After spending years in apartments during our college years, Chris and I became first-time homeowners and took to gardening in earnest. A modest collection of 19 irises arrived in September 2012 and were gifts from my mother Alleah. We planted them on the north side of the house where they would have good drainage and receive plenty of sun. Among these irises was 'Peggy Sue.' Alleah's description of this iris was deceptively plain: Peggy Sue - L. Lauer '06 - pink, red beard, lightly ruffled.  Although we didn't know it then, 'Peggy Sue' was destined to confuse and delight us. 

Several of our new irises bloomed the following spring, but 'Peggy Sue' wasn't among them. Her first bloomstalk appeared much later . . . in NOVEMBER! We were ecstatic to enjoy a flower in bloom, but also wrongly assumed this iris was confused. I posted a garden photo on Facebook, and included it in an e-mail to other members of the family.

Fall 2013

I suspected this bloom might be evidence of global warming, but my mother set me straight. Alleah was, and still is, vastly more knowledgeable about irises she chooses to maintain in a garden setting. Her response was, "I hate to burst your bubble, but 'Peggy Sue' absolutely knows it's November and is doing the right thing. She blooms EML and RE (AIS abbreviation for early, midseason, late season, and rebloom). . . . So whether or not I labeled the iris RE, she is. I'm attaching the October Santa Rosa Iris Society Newsletter in which I printed a long article on successful rebloomers in California and referred to a commercial garden in Virginia that specializes in rebloomers." 

Alleah's email continued with gems of motherly, irisey, and scholarly advice. "You may wish to go online and see a list of rebloomers in that geographic area and ask for some . . . .  Reblooming is a recessive trait. An iris breeder improves his chances of getting a rebloomer by crossing two rebloomers together, or involving several rebloomers in his line. 'Peggy Sue' has 'Pink Attraction' (RE) in its background, although none of the other irises in its background were registered as rebloomers. You will have to find other evidence of global warming."

Spring 2014

After planting some extra rhizomes of 'Peggy Sue' in the backyard, it became obvious that 'Peggy Sue' in the front yard had better growing conditions. These conditions led to more consistent bloom and rebloom in the front yard compared to the back. Rebloomers appreciate being watered throughout the summer. Frequent rain combined with a leaky hose spigot provided front yard 'Peggy Sue' regular access to water when she wanted it. She responded by blooming regularly and making lots of increases.

Fall 2014

Early Spring 2015

Very Early Spring 2016

Being located close to the foundation of our house also allowed for slightly elevated temperature. Bricks can absorb and store thermal energy from sunshine during the day. When the sun went down, the bricks slowly dissipate stored energy to their surroundings, including front yard 'Peggy Sue.' As years passed, we got several earlier- or later-than-usual bloomstalks, resulting in bloom for Thanksgiving and Christmas! Each time she bloomed, my inner Buddy Holly started singing, "I love you Peggy Sue, with a love so rare and true. Oh, Peggy, My Peggy Sue!"

Late Fall 2015

Winter 2015

Late Winter 2017

'Peggy Sue' was not the only iris we that rebloomed for Chris and me in Mebane, but it was one of the more memorable cultivars we maintained there. Of 80,000+ irises registered with the American Iris Society, about 4,246 (0.5%) are known to exhibit rebloom. By 2015, I was eager to get more rhizomes of reblooming irises. Unfortunately, many of the rebloomers I added didn't seem to like us very much. They didn't die, but only three of the twelve irises Alleah gifted to us demonstrated rebloom. I tried following conventional advice by providing more water and fertilizer, but most never bloomed more than once in a growing season. Thankfully we had better success with the rebloomers I purchased from Alleah's grower recommendation in Virginia, and from rhizome sales hosted by my local iris society. 

'Daughter of Stars', Late Summer 2018

'Bonus Mama', Early Fall 2018

Eventually, I learned that irises that rebloom in one climate (e.g., my mother's garden in California), may not be well suited for rebloom in another (e.g., my garden in North Carolina). I started paying close attention to Colin Campbell's work gathering rebloom data in my region, and combing through back issues of the Reblooming Iris Recorder for reports from gardens closer to me. I joined the Reblooming Iris Society (RIS) in 2021, and could access newer issues of the Reblooming Iris Recorder as they became available. While attending the National AIS Convention in Las Cruces, New Mexico, Alleah and I each purchased the 2022 edition of the Cumulative Checklist of Reblooming Irises. 

This must-have resource is available as a printed book, flash drive, and digital file sent by e-mail 

Alleah likes using paper reference materials and purchased the rebloom checklist as a spiral-bound book. I prefer having electronic reference materials and purchased a flash drive that contains a .pdf copy of the checklist, as well as a spreadsheet version of data used to create the checklist. I store the rebloom spreadsheet on my phone so I can access needed iris information quickly. The 2022 edition of the rebloom checklist builds on prior editions from 1975 and 1988, which contained 641 and 1,428 varieties respectively. To create these must-have iris resources, the Reblooming Iris Society engages in what I would call "citizen science." Iris enthusiasts, including hybridizers and iris lovers from around the world, voluntarily track the bloom and rebloom behavior for the named iris varieties each growing season. Next, volunteers share their rebloom data with an RIS Area Director who pools rebloom data and organizes it for publication in the Reblooming Iris Recorder, and subsequently in a checklist.

For years, I aspired to track and report my own rebloom data. However, I always struggled to find time and energy to do it. That is . . . until I remembered that I photograph most irises and their identification tags with my cell phone when they bloom. My cell phone records the date and location of my pictures automatically. EUREKA!

 

Earlier this year Mary Platner, editor of the Reblooming Iris Recorder, called and asked if I would be willing to track rebloom for irises growing at the farm in Ramseur. I was hesitant and explained that most of our irises are recently planted and receive no supplemental water. Mary lives in Scottsdale, Arizona and has her share of irrigation issues. She assured me that my rebloom data would still be valuable and I agreed to help. Bloom charts can be filled out on the computer or printed on paper. Mary provided me with an example chart, and her instructions were easy to follow. Each month is divided into three columns. If the day of the month an iris blooms is between 1 and 10, an "X" is placed in the E column of the appropriate month. Similarly, if it blooms between days 11 and 20, the M column is marked. Finally, if it blooms between days 21 and 31, the L column is marked.

Bloom Chart Directions 2022

Now that overnight temperatures on the farm are below freezing, our 2022 bloom season has ended. I'll use data stored in my phone to chart if and when my reblooming irises came into flower this year. When all is recorded correctly, I plan to email completed bloom charts to my assigned RIS Director and give Mary a heads-up that they are finished.

Hopefully, sharing our experiences will inspire you to add rebloomers to your garden and take part in data collection efforts. Working together, we can help everyone understand reblooming irises better, and rest easy knowing these genetically interesting plants are certainly NOT confused.

Irises of the Season

by Jean Richter

For this last post of 2019, I present to you a group of irises with seasonal names, pertaining to winter and late-year holidays. As might be expected, some of these varieties are rebloomers, and those will be noted with their picture. All iris are tall bearded unless otherwise noted.

My best wishes for a joyous and peaceful holiday season and happy new year! May the second century of the American Iris Society build upon the many great accomplishments of the first.

'Christmas Snow' (Austin 1963) rebloomer - photo by Mike Unser

'Snow Fiddler' (Dunbar 1972) miniature tall bearded - photo by Mike Unser

'Snow Velvet' (H.P. Sass 1942) - photo by Mike Unser

'Lacy Snowflake' (Schreiner 1977) - photo by Mike Unser

 'Winter Gold' (Austin 1965) rebloomer - photo by Mary Hess

'Snow Spoon' (Hager 1982) - photo by Mike Unser

'Winter Carnival' (R. Schreiner 1941) - photo by Mike Unser

 'Thanksgiving Firelight' (Austin 1950) rebloomer - photo by Mary Hess

'Santa's Helper' (Carol Lankow by Aitken 1997) intermediate bearded - photo by Mike Unser

'Winter Olympics' (O. Brown 1963) - photo by Mike Unser

'Winter Flame' (Austin 1953) rebloomer  - photo by Mary Hess

'Winterfest' (Schreiner 2005) - photo by Mike Unser

'Frost and Flame' (Hall 1957) - photo by Mike Unser

My heartfelt thanks to Mike Unser and Mary Hess for the use of their beautiful pictures.

Children of 'Over and Over'- Pt 1 -Breeding Rebloom Iris zone 6 KY

by Betty Wilkerson

In the world of iris hybridizers we often hear "you can't do that!" Gather information, learn all you can about the possible results, and forge ahead.  Even though some say "it can't be done," don't let them deter you from following your iris dreams.  Two beautiful parents may not produce exactly what you visualized, but you will make progress, and most important, you will learn.  One of the most important things you will learn is the type of children your parents will produce.   Whatever your goal may be, stay focused, stay aware of other advancements, and keep making those crosses. You can't plant them if you don't cross them!

Over the past 10 years 'Over and Over' is the strongest rebloomer here in my zone 6 garden.  I've asked several people if they were working with it.  Most replied that the iris was too plain or old looking.  I thought I'd encourage some, maybe, by showing some of the children I'm getting by using 'Over and Over' as the pollen parent.

'Over and Over' (Innerst 2001) (pollen parent)

2130-01re (Wilkerson seedling) 

The pod parent of 2130-01Re is a seedling from 'Again and Again' X 'Echo Location.' 'Again and Again,' and has some plicata in the parentage, while 'Echo Location' is from two plicatas.  I did expect plicata seedlings, and there were three.  Two rebloomed, but didn't add anything new to the vast group of purple plicata rebloomers or my knowledge of their genetic makeup. There were several interesting things in pale yellow with lavender splashes and streaks. The seedling above (01Re) was saved because the maiden bloom was a deep plum colored self. The next year it bloomed in August, but the color was more pale. The following year it settled into the above pattern and color.

2612-01re (Wilkerson seedling)

This seedling, 2612-01Re, has a bit more modern look than 'Over and Over.' Since this was maiden bloom, it will be years before the final determinations are made. By then I plan, and hope, to have many more seedlings blooming from this cross and others like it. On first glance it appears the seedling has better form than either parent.  Not all will be good enough for the world to see, but things are definitely looking up.

This is not enough to make any big declarations, but I suspect there will be more to come.  I'd like to branch out into other colors, as this is not my favorite.  Stay tuned.  Next, I'll try "Over and Over" as the pod parent.

If you have questions or comments, please add them below.

Working With Selfs-Reblooming Iris Program-Ky Zone 6

by Betty Wilkerson

Once again I've found an article to wrap around 'Summer Radiance.'  I'll never forget the first time I saw it bloom.  I was coming home from a Region 7 spring meeting.  The first stalk of what was to become 'Summer Radiance' was showing lots of bright yellow when I left for the meeting.  When I arrived back home, I dropped my suitcase on the back path and tore off down the hill to the bed by the pond.  I was thrilled with the blooms and have found more things to love about it in the 20 years since its introduction!

I was just as thrilled six weeks later when it put up a summer stalk.  That sealed its fate!  It would be with me forever! Twenty years after its introduction, I'm still using it in breeding.  I've done the research and know it does not produce plicatas.  A part of that research was growing nearly 200 seedlings from 'Summer Radiance' X 'All Revved Up.' Not a plicata in the bunch. This makes me happy, since I'm not fond of haft marks.

When breeding with pastels, this is one of my top contenders.  I can also use it when I want to inject some yellow into another line, with full understanding that I may get all kinds of rebloom, too.  I still want to turn the beard red, but I haven't decided what to use it with, yet.  'Summer Radiance' is from 'Lemon Reflection' X 'Hindenburg,' so it's only one step away from a red beard.  I would already have some results of breeding for red beards,  but I lost all of the seedlings from 2013. Maybe next spring.    

As 'Summer Radiance' grew in other climates, we discovered that it can fall or cycle bloom. It bloomed here in early July as repeat bloom.  Then, it bloomed early fall further north.  In Virginia, Mike Lockatell reports that it reblooms often and well, which is simply proof that you should never give up on a reblooming iris.  

When crossed with 'Radiant Bliss,' it gave 'Summer Honey' which can bloom from spring through fall frost. So, all told, 'Summer Radiance' is a pretty special reblooming iris.  It has probably taught me more about rebloom than any of my other seedlings.  

Hope your new year is filled with many gorgeous iris blooms.  Merry Christmas to all.  To all good iris dreams!

Dominance and Patterns in a Reblooming Iris Cross

By Betty Wilkerson

Most of you know that I’m not an expert on iris genes. I’m going to take you down my garden path so you can see some of my seedlings. The plicata pattern has never been my favorite. I didn’t have a lot of options in the beginning, or when the irises, and I, moved to Allen County during the fall of 2003. 

In the spring of 2004, a couple of the brightest blooms were ‘Radiant Bliss’ and ‘Summer Radiance.’  This was not a cross I’d planned, but it did make sense.  ‘Radiant Bliss’ is a tall, well branched rebloomer and tall, well branched iris make the best pod parents.  It's a fall cycle rebloomer.   ‘Summer Radiance’ had refused to set pods and was being used as a pollen parent.  'Summer Radiance' is without plicata in its geneology and it reblooms in July and then in the fall.  

Genetically speaking, solid color selfs are dominant over plicata.  What does this mean to people that have never made a cross?  When using a self, in this case 'Summer Radiance,' that has no plicata in the parentage, none of the children will be plicata.  The children will be a mixture of variegatas, bitones, bi-colors, and blends, with possible overlay or apron patterns.  Many will have lots of haft lines & murky colors.  

'Radiant Bliss' (Wilkerson 2005)
Pod Parent

'Summer Radiance' (Wilkerson 1996)
Pollen Parent

In a cross like this, many seedlings will be some version of a solid color.  Some will have haft lines, like the ones in these pictures.  Some colors will be clear, while others are murky.

(1814-01re)

(1814-03)

(1814-05)

More exciting, for me, would be the variegatas.  I had hopes one of these would rebloom, but no such luck.

(1814-06)

There were several red seedlings.  One (not this one) did try to rebloom, but really late.  I saw it as winter bloom. Haft lines were bad on the red ones.

(1814-08)

'Summer Honey' (Wilkerson 2013)

In the end, 'Summer Honey' (#1814-02re) was the star of the crop.  She fall bloomed for several years.  During the summer of 2011, after a lineout planting the year before, 'Summer Honey' bloomed each day from spring bloom until the first fall freeze!  It was a good sized planting, but still nice to have bloom all summer.  Could a good sized planting be the solution to continuous bloom?  

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.