The Autumn Iris Garden

by Tom Waters

Here in New Mexico, the autumn equinox has brought a chill to the air and a change in the light that says summer has gone. I thought I would write about a few aspects of iris gardening in the autumn.

Is it too late to plant bearded irises?

Allow at six weeks for newly planted irises
 to get established before the first frost

A good rule of thumb is that bearded irises should have at least six weeks to establish themselves before the first frost. Here, with average first frost around October 10, I certainly aim to have all my planting done by mid-September. Yet we've all been in situations where we get some unexpected irises at a sale or meeting or from friends late in the season, or just can't manage to get everything in the ground as soon as we'd like. The good news is that irises are pretty resilient, especially in areas where winters are not too severe. I've planted up to the first frost date without losing many. Things that just can't be planted should be potted up and placed in a sheltered spot to overwinter.


Should I trim back the leaves in autumn?

My leaves may look tired,
but please don't cut them!

Leaves and roots are both trimmed when digging and dividing irises, to reduce transpiration losses, to reduce demands on the already disturbed plant, and to make them more stable in the ground when replanted. Leaves should not be trimmed on established plants that you are not digging and dividing. I don't know how this practice got started, but it is not recommended. As long as leaves are green, they are photosynthesizing and producing food to strengthen the plant for winter. Trimming is not terribly damaging; the irises will survive it and still bloom next spring, but why set them back, even a little? I think some people like the tidy look of a neatly trimmed iris bed. (To be honest, autumn foliage can look pretty ragged and tired.) But I have enough to do in the garden just keeping up with chores that actually help the plants do better. I have no interest in doing a chore that makes them do worse, just for the sake of appearances or tidiness. An exception might be the foliage seems to be getting diseased, or if you are worried about possible rot or losses and want to get more light to the soil and air circulation around the fans. Mostly, though, such problems should be addressed by planting with proper spacing, and providing good summer care.


Should I fertilize?

A light top dressing of organic matter
helps feed the soil

Autumn and spring are when irises are in most rapid growth, so it is good to support them at this time of year with ample water and nutrients. As explained in an earlier blog post, there are good reasons to avoid synthetic fertilizers, especially if you have not had your soil tested and are not addressing a specific nutrient deficiency. I do apply a layer of partly composted mulch in the autumn (I usually try to do this a month or two before first frost), and sometimes also sprinkle on a blend of organic fertilizers. This encourages the soil life and improves soil structure. Since I also do this in spring, there is a more or less steady flow of decomposing organic matter into the soil. Autumn is a good time, because instead of drying out in the summer heat, the layer of organic matter will stay moist, and winter snows and temperature swings will help break it down.

If you are in a cold-winter climate where you use a heavy winter mulch to prevent heaving, it should not be applied now. Wait until the ground has frozen and winter is here to stay.

I collected seeds this summer. Should I plant them now?

Seeds from hand pollination and from
seed exchanges, ready for fall planting

Hybridizers grow irises from seeds (made mostly from planned cross-pollinations) to create new varieties, and sometimes hard-to-get iris species are available as seeds through seed exchanges. I plant my seeds around the time of first frost.This blog post covers all the basics of growing irises from seed. If you've never grown irises from seed before, it can be quite fun and interesting! A few words to the wise, however: named iris varieties do not come true from seed. Also, it takes about three years to get a blooming-sized iris from seed. So this is not an easy or inexpensive way to get more plants of your favorite irises. Division or purchasing additional rhizomes is the way to do that. Also, keep your seedlings separate from your named varieties. (If you plant seeds in the soil, that spot may be sprouting irises for a number of years. Do not plant named varieties there next year!) It creates trouble for future iris lovers if you get named varieties mixed up with unnamed seedlings, or circulate your seedlings among friends. Have fun, but be responsible with the plants you create.


Reblooming irises!

Historic reblooming iris
'Summer Whitewings' (G. P. Brown, 1960)

Some irises rebloom in the autumn after their normal spring bloom, and these can be a real joy at this time of year. September and October is the peak time for rebloom in most parts of North America. Different rebloomers are suited to different climates. If you want to start building your own collection to enjoy, check with the Reblooming Iris Society or with iris growers in your area. Rebloomers need water and nutrients during the summer and autumn, so do not slack off with your garden chores as the season wears on!

This is good advice for all your irises. It is tempting to "let things go" and fend for themselves as the days grow shorter (we all run out of steam at some point), but if you can give your irises the same level of care in autumn that you do in spring, they will thank you for it!

2016 Summer Rebloom in KY, Zone 6

by Betty Wilkerson

In my zone 6, Kentucky garden, summer rebloom is anything that blooms between the end of spring (approximately the third week in May) until the beginning of cycle rebloom in the fall (approximately September 15).  My last post discussed the late stalks, which I consider to be rebloom.  Now, on to the full summer bloom.  

The very first summer stalk I found was on 'Artistic Showoff.'  It is a sibling to 'Echo Location' and usually starts rebloom late, some six weeks after the spring bloom is over.  This year an established planting is also producing stalks later in the summer.  

'Artistic Showoff'' (Wilkerson 2013) 

After sending up a late beautiful stalk with over 11 buds, 1907-10Re has four more stalks. Unfortunately the last two, blooming in the extreme heat of July, have heat stunted stalks.  The stalks do not reach full height and the blooms are stacked on top of each other.  

1907-10Re (Wilkerson seedling) 

 'Summer Honey' has won "best specimen" in a fall show in Virginia.  The exhibitor was Mike Lockatell.  It has two stalks on one clump this summer.  One row was used and the other row is a bit under grown as the adjoining field imposed upon the plants.  It is usually well branched.  The first stalk was hit with a strong thunderstorm so the first couple of blooms were a bit mauled.  I am lining out the rest in hopes of more stalks next summer.  

'Summer Honey' (Wilkerson 2013)

'Over and Over' is really dependable in my garden when it comes to rebloom.  It's been in three different beds over the course of nine years and has rebloomed in all three locations. It has very clear and clean white standards and falls with a trace of blue/lavender along the edges.  Currently, a new clump transplanted in the fall of 2015 has two blooming stalks.  In the fall it is a very good foil for my own 'Star Gate', so I try to keep them planted together.  

  

  

'Over and Over' (Innerst 2003)

There was another stalk on 2611-04Re.  This is a total of eight stalks in approximately ten months, two stalks in the fall of 2015, four in the spring of 2016, one late stalk right after spring bloom ended and another in the early summer.  Another sibling, 2611-06, is showing color and should be open in a couple of days.  It appears to be much like 04Re.  

2611-04Re (Wilkerson seedling)

We've had a hot summer, but it's also been wet.  There have been about three weeks in which the night time temperatures have not been below 70 degrees.  This may have an effect on the fall rebloom.  If night temperatures are as important as we've come to believe, there may only be late fall rebloom, which can be frozen back unless the freezing temperatures hold off.  

My primary goal is to have rebloom before the late fall hard freeze.  Although I'm not really crazy about having blooms open in extremely hot weather, I can see cutting some stalks to bloom indoors.

Inside or outside, I've found my garden to be a wonderful place this year. Hope you have all enjoyed your gardens, too! 

Late Stalks: Rebloom Breeding in zone 6A

By Betty Wilkerson

Welcome to my garden.  I'm in Kentucky, zone 6.  Once again, it's been a crazy, crazy spring.  We had some really nice days during the last half of winter.  Good days to clean the iris beds and get ready for spring.  This is when it started getting crazy!  I suspect it was Mother Nature in stress mode, but maybe it was just the irises acting weird.  

Just a few days into the bloom season, it looked like a lot of the early things would not bloom!  Then, stalks started to spring up, or so it seemed, on the ones that should have bloomed earlier.  Everything was out of sequence.  However, it did make rebloom crossing easier because more flowers were blooming at the same time.  

At the end of bloom season, the inevitable depression set in.  It's generally over for another year (except for rebloom). Then I noticed extra stalks showing up. There were a couple on some of the new reblooming seedlings, and one on a slightly older seedling from rebloom breeding lines!

There's one on 'Cameo Blush,' and one on 'Over and Over.' 'Silver Dividends' also put up a stalk but with only two blooms.  (No other introduced irises bloomed at this time.)

'Cameo Blush' (Weiler by Friendship 1998)

'Over & Over' (Innerst 2003)  

Two of the seedlings from 'Tara's Choice' X 'Again & Again' put up stalks. The yellow one, 2152-02re, has cycle  rebloomed in the past and is in my older reselect bed with 2 stalks up.  2152-03 is from my previous "baby" bed and was not seen before.  It wasn't great.  No, I don't always plant all of a given cross at the same time. It depends on space and time, and what I want to see, but these were pretty and several rebloomed, so I planted all of them.


One of my disappointments has been 2527, a cross with 'All Revved Up' & X 'Lunar Whitewash.' 'All Revved Up' can bloom all summer and 'Lunar Whitewash' is a good cycle rebloomer, so I'd hoped for some type of rebloom, with good form.  I got form but none have rebloomed, yet. It was a bit surprising when some of these seedlings started putting up late stalks.

2527-05 ('All Revved Up' X 'Lunar Whitewash') 

2527-01 ('All Revved Up' X 'Lunar Whitewash)

2527-05 ('All Revved Up' x 'Lunar Whitewash')

 The latest developing stalks were 2145-01 ('Pure as Gold' X 'Summer Radiance') and 2603-04, a dark one from ('Lunar Whitewash' X Romantic Evening') X 'Over and Over.' A large group of 2145-01 crosses bloomed and were photographed in the spring, while 2603-04 did not bloom in the spring and this is my first time to see it.

2145-01 ('Pure as Gold' X 'Summer Radiance')

2603-04 (('Lunar Whitewash' x 'Romantic Evening') X 'Over and Over')

With three exceptions, all of the surprise reblooming has been on my seedlings which have at least one rebloom parent. My theory, and it's just a theory, is that I should take this as a signal that, if not rebloom, they have some type of "loosy-goosy" genes that allows later bloom.  One thing for sure, they don't put up these late stalks every year. Come to me, my favored children!

You've had another peek into the strange habits of mother nature as she works in and around Bridge In Time Iris Gardens.  For further reading about reblooming irises, visit the Reblooming Iris Society site  or subscribe to "The Recorder" through the website.

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.

Reblooming Iris Breeding in Zone 6 Kentucky-Cross # 2527

In this post we're dealing with dominant (selfs) and recessive (plicatas) traits and the resulting seedlings. There are many dominant traits and many recessive traits, but this will only deal with selfs and plicatas.  Lots of fun and a few surprises.

'All Revved Up' is one of my plicata rebloomers. It is a child of 'Radiant Bliss' and contains some genetic material for color from the west coast, mainly 'Gigolo.'  It has bloomed in all months from May through October.  'Lunar Whitewash' is a white reblooming iris introduced by Sterling Innerst. It is a good cycle rebloomer. Both are rebloomers and both have good form.  'All Revved Up' has good branching and bud count, but is a little short, while 'Lunar Whitewash' has great form, but really lousy branching.  The goal was a really good meeting of the genes and interesting colors.  

'All Revved Up' with 'Lunar Whitewash' behind. 

Pod Parent 'All Revved Up' (Wilkerson 2007)

Pollen Parent 'Lunar Whitewash' (Innerst 2000)

If you cross two plicatas you will get mostly, and usually all, plicata seedlings. With a decreasing number of plicata genes within the solid or self, you will get a varying number of plicata seedlings, but most will be selfs, bicolors and variegatas. If there are no plicata genes in the self, as appears to be the case with 'Lunar Whitewash,' there will be no plicatas, but there will be haft lines.  

2527-01 (Wilkerson Seedling)  

2527-02 (Wilkerson seedling)

The seedlings have varied with most being the same or near the combination of 2527-02. This is my favorite of the purples since it produces a large number of stalks and blooms.  The white one, 2527-01, is a bit taller with really consistent spring stalks, and probably my favorite of all the results.  Although any color is possible with this combination, the yellow, 2527-06yellow, came as the biggest surprise to me.   Lack of rebloom was the most shocking, but they were in a bad bed.  

2527-06yellow (Wilkerson seedling)  

In earlier years, plicatas provided a large part of the base for rebloom.  It should be no surprise when haft lines show up with plicatas x self crosses.  It's been explained to me that this is not a "plicata effect," as I'd thought, but simply that the lines are not considered a default in the plicatas so they were not bred out of them, therefore, they show up in the children.   

It's not uncommon for my gardening to overreach my ability to keep all of the beds clean of weeds, since I prefer breeding to weed pulling.  These pictures are taken to document flowers for my breeding program, and I never thought they would be viewed by the public.  Please forgive the weeds.

Rebloomers at Bridge In Time Iris Garden

After the Fall Freeze 2013 . . .

By Betty Wilkerson

 zone 6b in South Central Kentucky

It’s been an interesting year at Bridge In Time Iris Garden. Despite a fall freeze, and my inability to get into the garden much lately, some rebloomers have shown their beautiful faces through the weeds.  I have not fertilized for the past two years either, which has had an effect on the garden.  Weather was good for rebloom, but only a few faithful bloomed this year.  

Most of the larger, bloom-sized rhizomes were dug and sent around the country earlier this year. I have reports of some of these reblooming already in other areas. 

Bloom began here in late August with 1907-10Re.  In 2011, this was one of the two seedlings that bloomed all summer, but this year it didn’t show its beautiful face until late summer.  It was a welcome sight.  

1906-10Re Fall Overlay (Wilkerson seedling) 

Pretty as it may be, it does not always grow tall enough, and it's PURPLE.  Purple is a common color in reblooming iris.  Would you buy it?

1906-10Re-Beard (Wilkerson seedling) 

Currently, 'Over and Over' is one of the most dependable rebloomers in my garden. It wasn't the only one to rebloom in this difficult year, and it wasn't the first one to rebloom, but it did, and faithfully. I've discussed this with other breeders and many have said they won't use it because it isn't pretty enough, but I'd like to remind everyone that it is a really strong rebloomer.  Furthermore, when crossed on self irises it will not give plicata coloring.   

'Over and Over' (Innerst 2000) 

Toward the end of the season, but with plenty of time to open well, '2150-02Re' put up stalks. This is from 'Star Gate' X 'Matrix'.  Many seedlings from this cross rebloomed, but this one blooms the earliest and is most dependable.  Again we have the "dependable" quality, but not early enough, and PURPLE.  'Star Gate' is a dependable rebloom parent, but tends to breed only white or blue/purple with an occasional plicata.  Most often, this seedling will maintain the good fall form and also show an apron pattern like picture 2.

2150-02Re (Wilkerson seedling)

2150-02Re (Wilkerson seedling)  

Some might wonder why I've not made a cross between the two purple rebloomers.  Up to this point in time, I've not wanted to mix the beards.  '1906-10re' has many siblings and about a dozen have rebloomed. Same is true with '2150-02Re.'  With their parentage most of the seedlings would be purple and white plicata. Then there is the question on beard color.  There would be no chance of a tangerine beard.  Still, maybe next year!

Here are the seeds for 2013.  There are fourteen tall bearded crosses represented here!  They should start sprouting by April first, and I hope for lots of rebloom. Where there are irises and hope, there could be rebloom!

.

2013 seed crop

Exploring the Mysteries of Bloom Season & Height: Rebloomers

by Betty Wilkerson

Height

According to the American Iris Society, rebloomers must meet the same criteria that are stated for their individual classes.  My breeding program deals with tall bearded iris with the occasional cross in other classes.  The height qualification for tall bearded irises is 27 1/2" and above.  There is no upper limit stated, but an iris must stay in balance.  Many tall bearded irises have problems with falling stalks when the height is excessive. 

As you can see in this clump of 'Summer Radiance' (Wilkerson 96) there are stalks of various heights.  The stalks are measured from the ground to the top of the open bloom.  This should be done for a two year period.  The stated height is the average of these measurements in its home garden.

'Summer Radiance' (Wilkerson 96)  

As an introduction moves into the market, there will be some variations in the heights, and the iris may not reach these stated heights in the individual garden.  Soil contents, even micro elements, can change everything about an iris, including the height.  An early, hot season can create variations in height, too.

Spring Bloom Season

Tall bearded irises are the last of the bearded irises to bloom.  Season of bloom is designated within the tall bearded bloom season by VE for very early, E for early, M for medium, L for late and VL for very late.  These are determined in the garden of the hybridizer introducing them, and, based on my personal experience, may not be the same in your garden.  Again, VE means the iris should be one of the first tall bearded irises to bloom in your region and VL means the iris should be among the latest tall bearded irises to bloom.  These dates should be taken as suggestions, and may vary from garden to garden.  

It might seem that all rebloomers are very early (VE) to early (E) in the spring garden since they need time to bloom again, and indeed, most are.  'Star Gate' (Wilkerson 2005) is the only rebloomer I've introduced that isn't an early bloomer.  It blooms in mid season and can easily be used in breeding with later blooming spring only irises.  

'Star Gate' (Wilkerson 2005)  

As a hybridizer, you plan spring crosses during the winter.  The bloom season starts, but new acquisitions don't always bloom as hoped.  I rarely order very early irises because they can have a problem during a late freeze, although  I occasionally receive very early bonus irises.  So far, most of the new irises I've received with the VE classification are bloom EM in my garden.  

Rebloomers have pushed forward the beginning of spring bloom in my garden.  Here, tall bearded season begins with rebloomers and seedlings of mine that contain a lot of rebloom genes.  They will bloom for several days before regular spring blooming irises begin.  

In 2011 we had a light frost at the beginning of bloom season.  The blooms and pollen looked fine, but the pollen was damaged on open and nearly open blooms of 'Matrix' (Earl Hall by Lloyd Zurbrigg 1991)  'Echo Location' (Wilkerson 2007) and other open blooms.  When the frost hit, there were ten to fifteen stalks with open blooms on 'Lunar Whitewash'.  Crosses I made with this pollen did not take.  These are the difficulties faced by hybridizers working with early bloomers. It was three or four days before viable pollen was available.  

'Matrix' (Earl Hall by Lloyd Zurbrigg 1991)

'Echo Location' (Wilkerson 2007)

'Lunar Whitewash' (Sterling Innerst 2003)

By the time the late blooming irises are open, most of the rebloomers have finished blooming.  It’s hard to find anything other than ‘Star Gate’ to combine with late irises like ‘Iconic,’ ‘Haunted Heart,’ ‘Love Lines,’ or ‘Angel Among Us.’ Pollen from rebloomers can be stored in envelopes in the refrigerator for several weeks, but it’s such a busy time it’s often hard to remember to collect it!  

'Iconic' (Ghio 2010) Photo by Kent Pfeiffer

'Haunted Heart' (Keppel 2010)

'Love Lines' (Wilkerson 2006)

'Angel Among Us' (Wilkerson 2007)

Rebloom Season

My favorite rebloomers can bloom any time from the end of spring bloom until a killing frost.  To my knowledge, there is no correlation between the spring bloom season and the rebloom dates.  Rebloom can happen at any time and is determined by the genes of the cultivar, soil conditions, and weather conditions. There are only a few that can do this in my zone 6 garden during a normal season.  A few more can summer bloom in a moderate year, but few produce summer blooms in a hot and dry summer.  Cycle rebloomers are not genetically capable of summer rebloom and only rebloom in the fall when the temperatures cool and some fall rain has fallen.  

Additional information can be found at the American Iris Society website and the Reblooming Iris Society website.  Membership in the latter includes twice yearly publications called 'The Recorder.'  This publication reports rebloom from all over the continental U. S. and any other area that reports to them.

When do your rebloomers bloom?  Have you had summer as well as fall rebloom in your part of the country or the world?