New cultivars for New Zealand

By Maggie Asplet

I felt it was time to write about what I am doing and perhaps even be brave enough to say what I would like to achieve with irises in New Zealand.  

I have for many years been very interested in hybridising but found it rather uninspiring to use any of the over 1,000 irises I had growing at home.  They were all considered old (bit like me, really).  Sadly, due to our quarantine conditions it makes it virtually impossible to import irises into NZ, a situation that has been in place since 2004.  

We have relied on the generosity of others, like Barry Blyth, or to make crosses in America then they send the seeds to us.  The other way we have gained new seeds have been through guest speakers bringing them to our annual conventions - Chad Harris, Patrick Spence, Andi Rivarola, and James Geditz all brought seed with them.  Sorry, I know I will have missed some others.  We here in NZ are very grateful to you all (even those not mentioned).

It is with thanks to the generosity of Thomas Johnson from Mid-America for putting up with me, that I can finally get to follow my passion of irises and develop brand new cultivars.  I must also thank Paul Black and Keith Keppel for allowing me to pick their brains as well as their plants.  I just hope they can continue to cope with my questions.

 The excitement of a parcel arriving from Mid-America - March 2019

And a little more exciting seeing the packets of seed within the parcel

This arrived in March 2019

A parcel with so much promise.

I will start with standard dwarf irises. I must say that I am really taken with these delightful irises.  They make such a wonderful front of border garden plant.  To be fair, I'm not even sure what I personally would like to achieve other than to start off at home here in NZ with some lovely new cultivars.  Bright colours and strong beards is what I will be looking for with future crosses.  So many possibilities as Paul Black would say.

During 2018 I used some of the following SDBs in my crosses, and later this year I will post what I consider my successful outcomes, and continue to grow them with the intention of introducing them.  Hopefully by 2022 we should have the first ready for the general public to purchase.  Sadly, I haven't been able to do any MDB crosses as they are usually finished by the time of my annual trip.  I am rather partial to these little cuties.

 'Alaia' - T Johnson '18

 'Kerpow' - T Johnson '18

 'Slightly Tipsy' - P Black '18

'Color' - P Black '18

I must say it is rather strange for me to spell color like this in the US English style.  I want to do - colour.  

This is only a small selection of the SDBs that I used, these were the most successful in the crosses, and now only time will tell just what they will look like.

I did dabble a little with MTBs, and a couple of IBs and BBs but will leave them for a later stage, as did more on my 2019 visit.

My main focus has been TBs, what I considered everyone's favourite, until my eyes opened so wide and I saw so many other beautiful irises and not just bearded ones.  However, now onto TB irises. 

For these I used a wide range of cultivars as I wanted to get a variety of different new irises into the crosses I have done.  Many were very successful (seed wise), again, we still have to wait and see what this has achieved.  Here is a few of what I used.

Black X10A, which if my notes are correct is a cross between 'Beauty Becomes Her' X 'Haunted Heart.'  I will confirm my notes with Paul this year.

'Oh What Fun' - T Johnson seedling now registered

'Apricot Smoothie' - T Johnson seedling now registered

'Call Me Maybe' - T Johnson '13

'Charmed I'm Sure' - P Black '14

'Solar Burst' - M Sutton '16

'Bedroom Romance' - P Black '16

'Another Suggestion' - K Keppel '16

And, then I did a whole lot of crosses, some very wide and probably will not produce well with what I think is perhaps my most favourite color pattern (at this stage), the luminatas.  Here is what I used.

'Belle Fille' - M. Smith '15

'Dialect' - T. Johnson '08

'Fancy Ideas' - K. Keppel '13

'Montmartre' - K. Keppel '08

This is only an insight as I have begun my journey with with seedlings from newer iris and is by no means all that I have used.  These images are of irises where I have had successful crosses and now plants are growing.

One of the seedling patches.  These are now well established and hopefully will be in flower this spring (October).

It is not long now and I will begin my journey back to Mid-America, where I hope to concentrate more on some end goals rather than crosses for crosses sake.  I particularly want to work with SDB and MTB irises this year.  I somehow think that the MTBs might just become my favourite bearded iris.

SO, if you have a dream, make sure you follow it.  It is so much easier to toil away on something that you have a passion for than not.  Later in the year, I will write a blog about some of the outcomes, but will probably only show you what I think is successful.

To American iris lovers, your spring has begun, enjoy your beautiful season.

Convention 2019 - New Zealand Style

By Maggie Asplet

From the 15th of November through to the 18th of November, Irisarians from around the country and overseas gathered for three days of wonderful companionship, visiting beautiful gardens, attending workshops and the usual AGM and a delicious dinner and awards evening.

Friday evening is the time to register, check out who else is there and start talking about irises. This was a more informal evening with the newly elected local Mayor, Nigel Bowan opening proceedings for our annual event.  Our President, Marilyn Fleming also welcomed everyone.  We then had two short presentations from our two overseas guest speakers, Andi Rivarola and Gary White introducing themselves.  There will be more about them later.

From Left - Mayor Nigel Bowan, NZIS President Marilyn Fleming, AIS Vice President Andi Rivarola and AIS IPP Gary White

For me, the most special part was the book launch - Why Irises?  I trust you have all seen the earlier post about this book.  I was great seeing the team who had assisted the author, Gwenda Harris, make this all happen.

Marilyn Rathgen (at podium) gave background and introduced the team.  Stephanie Boot (also standing) was responsible for editing, providing many photos and layout and support and Alistair Boot had publishing responsibility.  Absent was Graham Menary also responsible for supplying photos.

There were a number of beautiful blooms on display, items set out of the silent auction and some beautiful memorabilia on display.

With the formality of the opening over, it was off back to our motels for the evening.

Saturday 16 November - a day out and about on the bus.  Yes, just one bus which was followed by a few cars.  We set off for the area of Geraldine for the day.

Our first stop was the the Geraldine Festival with many stalls all set out in the Domain for us all to wonder around, find a coffee and later get our lunch.

A beautiful outdoor solar light made from a stump; a new iris business "Irises of Kinvara", my favourite floral arrangement on display in a near by hall

Our next stop was to the home and garden of David and Lois Attwood.  This was also our first opportunity to purchase plants, and we did.  Like all iris bus trips, there is always room in the baggage lockers for plants.  A delightful town garden with many little treasures.  My favourite was the Moraea pictured below.

Pictures from David & Lois Attwood's

Moving onto our next garden of Bob and Libby Hall.  A beautiful older garden with some wonderful trees around, iris lining the left hand entrance of the the driveway and another opportunity to purchase some plants.  This was also a space of some wonderful and interesting sculptures, all of which were for sale.

I actually have a habit of going home from convention with a large item of my garden, or having to have it couriered home afterwards.  I can say that this time I was a little restrained and did not give into my usual buying habits (Large scale pieces to try and fly home with).

Pictures from Bob & Libby Hall's 

Our final garden for the day was at the property of Bernie & Joy O'Keefe and the home of Woodbury Rhododendrons.  This is very much a spring garden with some magnificent rhododendrons an numerous companion plants such as hostas, peonies, primulas, trilliums, hellebores and different edging plants.  Roses provide the garden with some wonderful summer colour.

As you wondered around this garden, we came across a lovely row of irises in full bloom.  I was also very taken with the pond area and water loving irises growing so well.

Pictures from Bernie & Joy O'Keefe's garden - Woodbury Rhododendrons

As is normal when attending a convention in New Zealand, we often are caught eating.  This was afternoon tea before we left for the trip back to Timaru and a free evening.

Saturday evening, although a free night, a few of us went out for dinner taking Andy and Gary for a bit of kiwi hilarity, topped of with our convention convenor feeding her face (sorry Marilyn).

Sunday, the day of staying put in Timaru, listening to some wonderful presentations by Andy & Gary on their trip to both Paris and Florence.  This was following by - guess what - time for mornig tea.

Shortly after this interval we held our judging workshop panel discussion with Gary and Andi on historic irises.  So very informative, on both counts and especially the Spuria irses, as we don't have much in the way of hybridising being done in this area.

After lunch, we held our Annual General Meeting - went without a hitch and didn't take long.  This was followed by the societies annual auction.  The South Canterbury Iris Group never disappoint in having a great selection of irises to bid on, and I sure did my fair share.

Andi checking out some blooms on display, then assisting Gary with one of their presentations and the group photo

The evening was our formal dinner at which time awards were given out, entertainment was provided by local member, Jean Barkman and then we were treated to another presentation by Andi on spuria irises.

Jean Barkman

Monday, a time to relax and enjoy the last of the gardens, so it was onto the bus again to travel south and visit members garden.  It was a day of dodging heavy showers and some hail storms that came through, particularly in the afternoon.

Our first garden of the day was at Lynda & Malcolm Crossen place in Southburn.  A beautiful garden with gorgeous iris display garden and also the irises that were entered for our New Zealand Begg Shield award.  This is judged during convention by approximately three judges.  Again, this is a garden with peonies, roses, hostas, rhododendrons, azaleas and so much more in, set in a stunning rural environment.

photos from Lynda & Malcolm Crossen's 

Our next stop was to Mary Brosnahan's garden.  Wow, this was just lovely, so well kept with the help of her daughter Susan.  I think the photos will say just how lovely this garden was.

AND - morning tea time

Back on the bus again to Lesley & Robert Tennant's garden at Otaio.  The property has been in the Tennant family since 1946 with many of the large Oaks, Elms and Ash already being there and since then the garden have been developed around this.  Definitely a garden that you need to wonder around to find some of the beautiful spots and areas framed with trees.  I even had an opportunity to talk with the chickens. The daffodils and the stunning pond are features of this property.

It is now 12.45pm and it is time for a short bus trip to the Waimate Events Centre - for lunch.  Before we got there, we had the first of some very heavy hail

From here it was onto our last members garden of Stephanie Boot's.  On the way, we have to "kill" a little time as the hail had again hit us, so we went around the block in Waimate looking at the Silos.

for more information - https://waimate.org.nz/visit-waimate-blog/silos

Just as soon as the hail had finished, we arrived at Stephanie's.  The very first thing you noticed was the huge amount of damage that the hail had done to her beautiful garden.  A gardeners garden, with some wonderful large Ash, Copper Beech and American White Oak trees.

Large specimens of Cordyline, Kowhai, Southern Beech, Totara, Chestnut, form the "bones" of this garden with Rhododendrons, Camellias, Roses and various other shrubs and natives.  Siberian irises now accompany the roses.

Hail on the ground when we arrived; Stephanie (facing us) talking with Andi, Gary & Marilyn; an iris not damaged by the hail

More garden areas at Stephanie's

It was also time for the official handover of the banner from the South Canterbury Iris Group to the 2020 hosts Bay Of Plenty Iris Group.  The banner was actually handed over on Sunday evening so that it could be taken bake to the Bay of Plenty by car.

This was a time for afternoon tea, thank you from different members and our two guest Gary & Andi.

South Canterbury Iris Group fare-welling us all

On our way back to Timaru we stopped at the Makikihi Display and Trial Gardens, which had not been spared damage from the hail storms during the day.

The Makikihi Trial and Display Gardens were established by the South Canterbury Group in 2008 under the enthusiastic guidance of Brian Harris.

Now Lynda Crossen, with assistant Stephanie Boot, is the Director of the TB Trial Gardens and the Group, under the supervision of Jessica Ward, maintains the Display gardens which contain Dwarf, Median and Tall Bearded, Siberians, Spurias, Louisianas, bulbous and some species and historics.
Potted irises and plants are for sale all year round.

SO, this is a little insight into a New Zealand Iris Society Convention.



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Why Irises?

By Maggie Asplet

It’s here, the eagerly awaited and definitive book on irises; many iris lovers have waited a long time for Gwenda Harris to put pen to paper and give the world the benefit of her huge experience growing these amazing plants.

Gwenda is widely respected for her intimate knowledge of irises and has travelled worldwide following her passion. Her talks and demonstrations have entranced audiences throughout the country and encouraged many to look further into the breeding, growing and showing this wonderful plant.

The combination of Stephanie Boot as editor with assistance from Tony Hall, with beautiful photographs by Gwenda, Stephanie, Judith Neilson, Graham Menary and Alistair Boot makes this a book to cherish. Why Irises? is not limited to just tall bearded varieties, but encompasses all the other members of the genus too. Gwenda, Stephanie and Tony are all well known in the iris world and have all traveled to lecture or to judge irises in worldwide competition.

This is a book for every iris lover's shelf, the stories of travels, talks given and general helpful hints contained within, make it a must have.

It’s available from the publisher Alspix Studios email   alistair@alspix.com  at a cost of NZD$35 a copy plus postage as follows:

New Zealand wide       $6.50

Australia                      $12.00

USA                            $22.00

Europe                         $22.00

Other countries by arrangement.          

  

To order please make full payment to the South Canterbury Iris Groups bank account - Westpac

# 03 0887 0290597 00   using your name as the reference. You can also use PayPal - apix@internet.co.nz.
Please also email the publisher with your postal address and confirmation that you have made payment.

Books will be dispatched in the order payments are received and as this is a limited edition be early to avoid missing out.

About Gwenda Harris M.A., B.Sc (Botany & Geology)

In between several false career starts, university study and some travels, Gwenda trained as an Editor with the DSIR (Department of Scientific and Industrial Research), was Field Officer for the Nature Conservation Council, then Executive Officer for the Environmental Council.  This was followed by working for the Nature Heritage Fund and the New Zealand Conservation Authority.

She edited the New Zealand Iris Society Bulletin for seven years from September 1993, and Spectrum (newsletter of the Species Section for NZIS) from March 2001 to March 2002.  Gwenda was awarded the Festival Crown Plate in 2001 for meritorious service to the New Zealand Iris Society for the producing the Bulletin and dealing with ERMA (Environmental Risk Management Authority) regarding the importation of iris seed - resulting in a further one hundred and six species being added to the list of species permitted for importation.  In 2016, Gwenda was awarded the President's Trophy.

Dykes Medals in New Zealand

By Maggie Asplet

The New Zealand Dykes Medal can be awarded every second year by the British Iris Society on the recommendation of the New Zealand Iris Society.

This medal is awarded also in the United Kingdom, United States, and Australia.  The Australasian Dykes Medal was first instituted in 1985 and allowed a medal to be awarded to New Zealand and Australian irises in successive years.  However the process of sending iris out of the country to be tested in Australia proved unworkable and as a result in 1992 the New Zealand Dykes Trial Garden system was set up.

 Frances Love holding her Dykes Medal

Picture thanks to Piki Carroll

Frances Love won the first New Zealand Dykes Medal in 1995 for the Siberian iris ‘Emma Ripeka’.  This iris is registered as 91 cm (36”) in height, with a mid-season bloom (October/November in NZ).  Standards are medium blue, style arms are sky blue and the falls are dark blue.  This is a seedling crossed with self.

It would take another 10 years before another Dykes Medal was awarded in New Zealand.

Iris 'Salute D'Amour'

Shirley Spicer first registered her iris “Salute D’Amour”, a Tall Bearded iris in 2001, and was awarded the New Zealand Dykes Medal in 2005.

This iris is described as being 84 cm (33’) in height and late season flowering (November in NZ).  The standards are light pink blush, styles arms soft coral pink and the falls are warm pink blush with soft white haft marking and a coral beard. This iris has a sweet fragrance.  Parentage is ‘Elysian Fields’ X ‘Flirtation Waltz’.

Seven years later the third Dykes Medal was awarded.

Iris 'Norma of Irwell'

Having registered his first iris in 1969, Ron Busch would have to wait until 2012 to be awarded his Dykes Medal for ‘Norma of Irwell’.

‘Norma of Irwell’ is a Tall Bearded iris first registered in 2008 and named after his wife.  It is described as being 86 cm (34”) in height, with late midseason flowering (Late October/early November).  The standards and style arms are deep purple and the falls deep violet-purple with white around the beard.  Beards are bronze tipped violet.

Finally, our fourth Dykes Medal was awarded just two years later in 2014.

Alison Nicoll holding a stem of Iris 'Atavus'

‘Atavus’ a Tall Bearded Iris bred by our very own President, Alison Nicoll, was awarded the Dykes Medal, at our Convention in Hamilton (2014).

Originally registered in 2006, ‘Atavus’ is 72 cm (28”) tall, a mid season flowering iris.  It is cream flushed lilac in the centre, style arms creams and lilac, the falls are strongly washed violet, has tan hafts and border; the beard is red.  This iris is flared with slight spicy fragrance.  Parentage is ‘Prince George’ X ‘Outrageous Fortune’.

How does our Dykes Medal System work in New Zealand?

Eligibility - Any New Zealand bred iris is to be eligible for testing.  Each enter is allocated a number, which is it knows as for the duration of the trial period.

Iris which have won the Begg Shield, McLachlan Trophy or the Lucy Delany Memorial Award should be sent to the Sykes Test Garden.

Entry – To enter plants for assessment send 1 preferably 2 rhizomes to each Dykes Test Garden.  No more than three different iris per breeder will be permitted in one cycle.

Judging – In the first year the iris will be allowed to settle and will not be judged.  In the following two seasons they will be judged by a panel of three judges which must include a senior judge, co-opted by the Director of each garden.  This may require several visits over the bloom season.

A copy of the judging papers is sent by each Test Garden Director at the end of each season’s judging to the Test Garden Co-ordinator for collating.  The average of the two seasons judging of each trail plant will be used to determine its performance in each of the Test Gardens.  The co-ordinator will then average the best two results from the three test gardens to determine the final number of points of each plant.

Growers will be given the results of their iris from the first year of judging on application to the co-ordinator.  Points are not published.

An iris which receives 70 points is eligible for an Honourable Mention; 75 points for an Award of Merit.

A Dykes Medal winner should receive 80 points or more.

Talking About Arilbred Irises

By Maggie Asplet

Aril and Arilbred Iris are not something that you would expect to see a lot of in New Zealand.  We are very fortunate to have Bill Dijk and his wife Willy, living in Tauranga, North Island of New Zealand.

Bill is one of those very lucky people with green fingers.  Whatever he does, it just works and is very able to get the impossible to be possible in our climate, with a lot of hard work I must say.

This article was been written by Bill and he has given me permission to publish his take on Aril and Arilbred Irises.

I. acutiloba susp. lineolate growing in coarse material.

When we talk about the aril irises, two very different types of irises are grouped together under the term "aril".   These are the oncocyclus and regelia irises of the Near East.  Although they have beards, they are not classified with the other bearded irises because they are so different in their makeup. Aril irises have derived their name from a little cream aril or a collar-like fleshy appendage of their seed.

Aril seed cut - showing the embryo

The arils show dark signal spots below the beards with much veining and speckling, in an unbelievable range of colours. Unfortunately, the arils are difficult to grow in all but the warmest and driest regions of New Zealand. I will start off by showing a few true aril oncocyclus/regalia species.  

Close-up of spcekling on I.samariae x I. hermona) X I. kirkwoodiae

In this century, hybrids were produced from crossing the arils with the more common bearded irises. These are called "arilbreds" (ABs), and are usually very easy to grow and still display the spectacular features of the arils. The arilbreds are as diverse in colour and form as they are in their genetic makeup and the combinations of these features make this an exciting and challenging group of irises. Unlike their aril ancestors, arilbreds can be grown successfully in a wide range of climates. They give gardeners the opportunity to enjoy the beauty of aril-type flowers without having to provide the special environment the pure arils require. They usually bloom earlier than the TBs, with the SDBs and the IBs.

I. Sheba's Jewel

Culture of Aril and Arilbred Irises

Arils and arilbreds have a reputation for being difficult to grow. This is partly deserved, but also partly the result of misunderstanding. Unfortunately, the word aril is often used rather carelessly to refer to both arils and arilbreds.  These two types, however, are very different in their cultural requirements and their capacity to grow and thrive without special attention.

Growing the pure arils like the oncocyclus and regelia species successfully is a real challenge, and it’s often a question of understanding their cultural requirements and adjusts them accordingly. Not always easy with our sometimes excessive wet, and humid climate in the Bay of Plenty in New Zealand. A warm and dry climate like central Otago would be more suitable, somewhat similar to their native habitat.

I. paradoxa atrata. Note its small, dark purple falls.

Today's AB’s (arilbreds) are not hard to grow in most climates. A selection of arilbreds interspersed among a bearded iris planting will find that most of them will grow and flower without any special attention; however, some understanding of  their cultural preferences increases the odds, ensuring a greater rate of success.

Although pure arils are not widely grown, a quick review of their cultural requirements is valuable, because it casts some light on the needs of their arilbred descendants.

The aril irises are the oncocyclus and regelia species from the Middle East and hybrids having only aril irises in their ancestry. The oncocyclus in particular have always posed a challenge to gardeners living outside their native region. They go completely dormant in the summer, which leaves them susceptible to rot in rainy climates. Furthermore, they don’t apologise for being temperamental, sometimes thriving for four or five seasons and then simply dying for no obvious reason. Regelia’s are much more adaptable, but still prefer dry hot summers.

Many different methods have been used for growing/protecting oncocyclus irises, especially during their summer dormancy when they must be kept dry. In cool, wet climates, most growers make use of a shelter/cover/frame, greenhouse or any other form of protection. I build this structure (picture) which is open on both sides for extra ventilation, and elevated bed for extra drainage, that is covered with polycarbonate plastic cover to keep the rain out.  I prefer to leave it on all season in our New Zealand climate to control the often excessive rainfall, warm temps and high humidity at the wrong time during the summer, which could results in rotting of the rhizomes.

Raised protected bed for Arils

This way I do control the cultural requirements like watering when needed, air circulation, feeding, and spraying for any fungal or insect problems.

Knowing the cultural requirements of the pure arils, one can take a few basic steps to improve the rate of success with arilbreds. If you have a choice of planting locations, arilbreds should be placed where light and air circulation are best and where drainage is particularly good. Take steps to avoid or reduce excessive soil acidity. Don't make the mistake of coddling them in a sheltered corner for protection from winter cold; such locations may be shadier and damper during the summer months, and lead to more harm than good. It will not be necessary to dig them or protect them totally from rain during the summer, as most arilbreds do not go completely dormant and are not as vulnerable as the pure arils. However, it is still wise to practice very clean culture and keep an eye out for densely overgrown clumps that could benefit from division. Plan on dividing arilbreds every other year; you may even find a few benefits from annual division!

In general, arilbreds of less than half aril content (this includes most arilbred medians) are to be grown exactly like the bearded irises. Giving them special treatment is unnecessary and may even be harmful, if it causes you to depart from tried and true practices that your bearded irises thrive on.

Those of more than half aril content should receive some preferential treatment. They should not require the full-blown summer protection preparations demanded by the pure arils but will appreciate the best drained, most open, preferably slightly raised location your garden can provide.

Preparing the site

For all arils: first and foremost, sharp drainage is important and the prime requisite for successful culture. They are desert plants, so they need full sun for at least two-thirds of the day. If possible, some protection, or shelter, from rain and cold is helpful.

Washed brick sand, granite, course pumice, or other coarse material, can be worked into the soil to improve drainage. There should be a good supply of calcium. (Gypsum can be used to provide calcium and loosen heavy soil.) If the soil is acid, lime should be added. Planting the irises on hills or ridges can help the drainage in marginal soils. Many people plant arils in raised beds where sharp drainage can be "built in."

To summarise:

•   full sun
•   sharp drainage
•   no water in summer for the pure aril irises while dormant.

Normally, the colours of aril blooms are extremely pure as well as clear. Alternatively, their blooms may even have wonderful blotches that contrast the colour of the flowers. When arils are hybridized with the standard bearded irises, the progenies retain a number of these attributes, while some other progenies may have new, but mesmerizing hues, patterns and streaks.

The falls of aril flowers have another typical characteristic. They may have veins and dotting or stippling in subdued or strong shades. These features may also appear in the standards of aril flowers. The dark, circular spots, also known as "signal", which appear at the end of the falls, are another typical trait of the flowers of oncocyclus irises, which distinguishes them from other iris flowers.

Iris mariae

Ideally, arilbred irises should be planted when they are just getting out of their hibernation or dormant period. You should avoid planting irises during the summer heat, as it is very stressful at this time of the year. Similarly, irises should not be planted during the late autumn just before the harsh winter months. In fact, the best time for planting irises is actually subject to the climatic conditions in your region.

Classification:  Nine Types of Arilbreds? Yes, Really

Although for awards purposes, the American Iris Society sorts all arilbreds into only two classes (less than 1/2 aril content and 1/2 or more aril content), the Aril Society International uses a more detailed system of categories that tracks not only the amount of aril content, but also the type of aril content (oncocyclus, regelia, or both).  

Close up of Iris paradoxa

An arilbred with only oncocyclus and bearded ancestry is an oncobred (OB). One with only regelia and bearded ancestry is a regeliabred (RB). If both oncocyclus and regelia ancestry are present, it is an oncogeliabred (OGB). This is by far the largest category.

If the arilbred has less than 1/2 aril content, it is marked with a "-" sign. If more than 1/2, with a "+" sign. If it has 1/2 aril content exactly, neither a "-" or "+" is used.

Aril seed as a rule are not easy to germinate, and there are several methods of germination:

Stratifying,  cutting and forced germination.  Aril iris seeds can be germinated with the following technique.

Forced germination" this is a technique that is often used for pure aril seeds to hasten germination. This method bypasses the need for any cold treatment.  The forced germination procedure involves cutting  with a scalpel or razor blade across the micropyle, across the end of the endosperm and embryo, in order to create an artificial rupturing of the micropylar barrier, which in natural situations germination could take a long time sometimes years to archive.  I use a special sharp grafting knife which I find personally more reliable and safer.

After soaking the seed for a few days in water (with some fungicide) to soften the seed, the aril and half the seed coat is removed, followed by cutting or slicing enough of the endosperm to expose the end of the embryo. I also borrow my wife’s art-craft 5X magnifying desk lamp with build-in lights for more close-up, hands free detail when slicing or cutting the seed.  

Most people do not do this with arilbreds, which germinate more easily.

Some people would try to stratify them and see what germinates first.  Sometimes temperature cycling is used as well. After all of that you could then try cutting or slicing them for faster germination. Be sure to sterilize the seeds before cutting them, especially for fungal protection when germinating seed in plastic bags or damp sterilized paper towels or whatever method you decide to use.

Points to recommend and remember:

1.   Hydration: Soak the seeds for up to a week in water with systemic fungicide.

2.   Remove the aril carefully (if it's an arilated species), cut the skin and slice a little layer to expose the embryo, which will be visible in the little hole of the endosperm.

Slicing aril seed

You need to be careful not to slice off too much of the embryo or you will negatively affect root formation and also risk damage to the embryo.

3. After cutting, put the seeds in damp perlite or vermiculate in little plastic bags.

I prefer damp sterilised kitchen paper towels for germination.

4.   When germination takes place in 2 or 3 weeks -

I prefer to very carefully transplant the little delicate seedlings directly into a 7cm X 9 cm peat pots, with a spray of systemic fungicide, outdoors in a cool, frost free place. Peat pots have the added advantage of no root disturbance when planted on into its permanent place or suitable container.

Having initial success with the germination, either forced or the traditional method is just the start of further necessary and ongoing special cultural treatment of the beautiful oncocyclus/regalia group.

After cutting/slicing I prefer germinating the seed in damp folded sterile kitchen towels, the moisture content when damp imho is just right for steady germination.  I then place the folded kitchen towels in an ice-cream container with the lid securely in place to prevent moisture loss, in a cool part of the nursery ( 10-15 C ). I inspect the seed at regular intervals for any sign of germination, with many seeds showing a radicle after 2-3 weeks in the damp kitchen towels.

I then proceed to very carefully prick out the sprouted seed, one at a time, in a 7cm X 9cm cm peat pot with 50/50 mixture of compost/fine pumice, water carefully to settle in the little seedling properly. Usually the seedlings ( 5-10 cm) will be ready for transplanting in its permanent place after 4-6 weeks. The very important advantages of the peat pots is no transplanting shock to the delicate seedlings, roots will easily penetrate the peat wall with no loss of growth. Don’t forget to spray the young seedlings with an appropriate fungicide at regular intervals for any possible fungal problems.

As is often the case with any specialist area of horticulture, complacency is the biggest killer and there is no substitute for constant observation, care and proper treatment.  The Oncocyclus and Regelia irises constitute an incredible group of plants that deserve nothing but the best.  The sight of just a single flower takes your breath away and a sight to behold.

To quickly summarise again :

    full sun.

    sharp drainage.

    dry for the pure aril irises, no water in summer while dormant.

These are some cultivation notes on how to grow the beautiful aril and arilbreds irises.

Editor's Note: For more information about aril and arilbred iris, contact The Aril Society International.  For more information about irises in general, contact The American Iris Society.