Iris cristata and small woodland Iris

[WimB]

Back from a week of training in Dallas Texas for my job, I noticed my newly purchased Iris cristata 'Montrose White' most leaf fans had collapsed and detach at the slightest touch. There were a few small slugs around the pot, which I disposed of, I suspected they were the culprit.  Overnight, the rest of the leaves were damaged and fell off, I think more is going on.  I washed all soil off, looking for view weevil larvae or adults, found none, but directly below where I was working I found a brown marmorated stink bug (an invasive here) that may have been the source of damage.

The roots are still looking healthy, so I will replant this someplace and hope that the now naked rhizome rejuvenates.

  I'm pretty sure they will regrow, though!

Iris gracilipes 'Cobblewood Charm' is in full bloom, floriferous and elegant.  This introduction by Darrell Probst is a hybrid between the dwarf white form known as "Buko" and regular I. gracilipes, this selection inheriting some of the compact size from "Buko".  The flowers are beautifully marked.

Super form, Mark!

[McDonough]

Collected seed today on 5 varieties of Iris cristata plus 1 pod each on two varieties of Iris verna.  Given that the Iris patches flowered well this spring, it is surprising that so little seed was set.  Last week I harvested 1 pod on I. koreana and about 6 pods on I. odaesanensis.  Thus far I have had limited success growing these woodland Iris from seed, odaesanensis yielding best germination, but that said, germination is generally very low with all of them.

So, I must experiment with different sowing techniques, to see if I can improve germination rates.  All of my meager harvest will be sown (sorry, not enough seed to share this year).  If anyone has suggestions for sowing techniques with woodland Iris, I would be grateful to hear.

Iris cristata stems and pods collected in plastic bags, where they will be allowed to open on their own.
Checking a couple sample pods, they seemed ready to harvest.

[cohan]

Mark, have you read the threads on SRGC about surgery on iris seeds? Folks were doing complicated things to cut through seedcoats etc..

[McDonough]

Mark, have you read the threads on SRGC about surgery on iris seeds? Folks were doing complicated things to cut through seedcoats etc..

No, I haven't seen those threads.  Can you point me in the right direction with a URL or two?

[cohan]

I was hoping you wouldn't ask that...lol-- it was quite some time ago I saw them, and now don't remember for sure if it was  a seed thread or in Irises, I think the latter, but I'll take a look if my internet connection co-operates.. if nothing else works, Maggi may remember..

[cohan]

Okay, I think it should be in this thread- can't go through all the way, right now, but another reference to cutting the seeds on SRGC mentioned this thread:
http://www.srgc.net/forum/index.php?topic=847.0

[RickR]

I've read about cutting seeds of aril irises, but never heard of it used for any of the other species.  Although, Rafa seems to think it could work on any genus.  Perhaps it is only because the aril type irises are notoriously difficult to germinate, apparently, that it's only been tried on them? 

Not that I have had great success germinating iris in general, but I have had better luck with I. odaesanensis than I. koreana, too.

[McDonough]

Earlier I posted about the surprising quick germination of Iris odaesanensis this year; never before did it germinate in mere weeks after sowing, normally waiting until the following spring to germinate. Originally showing 18 seedlings, the quantity has now doubled to about 36 seedlings.  Today I checked a small pot of Iris koreana (despite heavy flowering, only harvested one viable seed pod with 6 seeds inside), and 3 of the 6 seeds germinated, again just a few weeks after sowing.  

I believe I now know the recipe for speedy germination.
1.  sow seed immediately when harvested, in a good humusy soil.
2.  cover seed lightly with soil and top-dress with thin layer of decomposed pine bark mulch.
3.  place seed pots outside in a shady location.
4.  expose pots to 2"-3" of torrential rainfall each night for 3 weeks, followed each day by HOT HOT steamy weather

[McDonough]

Today I planted out 41 seedlings of Iris odaesanensis; I was surprised to see how well developed the roots were.

[RickR]

Wow, very impressive vigor on those plants!

One year we had a speaker on iris for our mid March Chapter banquet.  I was instrumental in securing the speaker, so I knew well ahead of time that he would be presenting.  The spring before, I potted up many small iris as door prizes for the banquet, and they included Iris cristata.  In early September I potted several more Iris cristata.  They all stayed outside for the first part of the winter, and I forced them inside the house, hoping to coincide the bloom with the banquet date.  God was smiling, and it worked perfectly.  I had blooming and budding plants to give away! 

The point of this story is that while every spring potted Iris cristata thrived, every fall potted Iris cristata died.  Mine were all divisions from mature plants.  With your plants being such vigorous seedlings, hopeful the same scenario will not apply.

[McDonough]

I was surprised to see just how developed the roots were after a mere 5 weeks from germination, but figured we still have September and October for them to keep growing and become established.  Never had seed of I. odaesanensis and koreana germinate in summer so soon after sowing, so I thought "what the heck", might as well experiment and plant them out.  I also planted out the small pot of I. koreana that germinated (4 out of 6 seeds came up).  I have plenty of each species, so if they don't make it, it'll be a lesson learned.

The growth of these species is different than I. cristata, having a thick "turf-like" habit, maybe they'll become established and overwinter more easily than cristata. 

I've never tried moving or dividing I. cristata in late summer or autumn, was thinking about moving some that are encroaching on some Trillium seedlings, but after your story, think I'll hold off until spring.

[McDonough]

I'm pleased to report that all of the seedlings of Iris odaesanensis and I. koreana that germinated in just a couple weeks after sowing last summer, and planted out in the garden in September, are alive and well, and sprouting into strong new growth.  Shown here are just some of Iris odaesanensis seedling plants.

[McDonough]

Iris cristata forms are on the move, sprouting quickly.  In fact, some are encroaching a sown-in-place bed of Trillium pusillum var. alabamicum, so I will remove the advancing rhizomes and pot them up for next week's NARGS plant auction.

The mat of I. cristata 'Edgar Anderson' also looks like it will need to be curbed this year, more material for a plant sale. In this photo taken recently, you'll get a good idea about how to grow this species; it is with rhizomes *above* the soil, it will root where it wants to, but the rhizomes are bone hardy even though fully exposed.




This is a dwarf seedling selection of Iris cristata, never bloomed in the 4 years I've had it, but I'm so anxious to see what the flowers are like.  The foliage is about 1/3rd-1/4th the size of normal Iris cristata.  Also, the rhizomes branch much more frequently. I will follow up with a photo if it blooms.

[Lori S.]

Iris cristata... In this photo taken recently, you'll get a good idea about how to gow this species; it is with rhizomes *above* the soil, it will root where it wants to, but the rhizomes are bone hardy even though fully exposed.

Very interesting growth pattern, Mark.

[McDonough]

Last year seed formation on Iris cristata was sparse, so the little I was able to gather was sown in a flat from "mixed" cultivars. My experience growing these from seed is hit or miss, sometimes decent germination, other times none at all. I noticed a couple days ago, seedlings are showing, hard to tell, but about 25 seedlings so far.