Iris cristata and small woodland Iris

104 posts / 0 new
Last post
RickR
Title: Moderator
Joined: 2009-09-21

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.

Rick Rodich    zone 4a.    Annual precipitation ~24 inches
near Minneapolis, Minnesota, USA

Mark McD
Title: Moderator
Joined: 2009-12-14

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 ;)

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Mark McD
Title: Moderator
Joined: 2009-12-14

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

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

RickR
Title: Moderator
Joined: 2009-09-21

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.

Rick Rodich    zone 4a.    Annual precipitation ~24 inches
near Minneapolis, Minnesota, USA

Mark McD
Title: Moderator
Joined: 2009-12-14

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.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Mark McD
Title: Moderator
Joined: 2009-12-14

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.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Mark McD
Title: Moderator
Joined: 2009-12-14

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.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Lori S.
Title: Moderator
Joined: 2009-10-27

McDonough wrote:

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.

Lori
Calgary, Alberta, Canada - Zone 3
-30 C to +30 C (rarely!); elevation ~1130m; annual precipitation ~40 cm

Mark McD
Title: Moderator
Joined: 2009-12-14

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.

Mark McDonough
Massachusetts, USA, near the New Hampshire border USDA Zone 5
antennaria at aol.com
 

Longma
Longma's picture
Title: Guest
Joined: 2012-11-19

Are you sowing into straight composted bark there Mark? Or is that just the mulch?
The results look very good. What is your watering regime please?

53.69° N, Dedicated to West Coast Fritillaria, plus three other members of the subgenus Liliorhiza. I grow other Genera, as time permits !

Pages

Log in or register to post comments