Iris cristata and other small woodland Iris

[TheOnionMan]

Thanks Mark, some great information so that I can translate it to UK conditions - are your winters exceptionally dry or wet?

Peter, you asked if my winters exceptionally dry or wet.... YES   Very hard to answer that question, but I will say that many evergreen plants here can die or be scorched from exceptionally low-humidity dessication... strong incessant wind for days on end yet with deep arctic freezing.  We typically have snow cover that turns to hard-pack ice like conditions, but snow cover can be unrealiable, then periods of winter rain can be detrimental, exacerbated by the fact the ground is frozen but the top few centimeters might thaw and become water-saturated.  Regarding the Iris, they grow in very open aerated layer of decomposed bark mulch, invariably in an elevated (mounded or bermed) location, most often sloped, all for positive drainage.  I find winter wet, and most importantly spring wetness, to be the most damaging or risky conditions for plants, and I try to err on the side of providing dryness and drainage accordingly.

[TheOnionMan]

It seems that China has many lovely Iris. At a recent garden tour at Joe Pye Weed's Garden, the amazing garden and nursery of Marty Schafer and Jan Sacks here in Massachusetts, USA, there was a planting with numerous Darrell Probst Iris collections from China.  I show just one such collection in bloom that day, a gorgeous little woodland Iris, among many listed as "Iris species novum" along with a collection number.  I hope some of these lovelies make it into horticultural commerce soon, and knowing of Jan & Marty's cultivation skills, and of Darrell's, maybe we won't have to wait too long.

There were many such clumps of various Iris species novum there; one had black stems and striking black bud spathes, the outer side of the ready-to-pop buds were light yellow, although Darrell assures me it opens to a light blue flower.  My photos on that one can out lousy, so I only show this one photo.

However, I have uploaded a photo of Iris gracilipes 'Cobblewood Charm', a 2008 Joe Pye Weed's garden introduction, a cross between the I. gracilipes "Buko Form" (tiny miniature white form, found on Buko San [mountain] in Japan) and the regular taller blue-violet form.  In flower it is about 6-8" (15-20 cm) tall.

[PeterT]

Thanks for the details Mark, I have been keeping an eye on Jan and Martys web site, I can feel another order from them coming on

[mark smyth]

Mark you have a stunning collection of Iris!

[Lesley Cox]

Thanks for all these incredibly exciting pictures Mark. I am deeply envious of them all as henryi, odaesanensis, koreana and some others have probably never been seen in NZ which means they never will be. Nor do we have any named forms of cristata, gracilipes or others you mention here, so far as I know. You are growing them exceptionally well too. It must be a great thrill each year when they flower.

[TheOnionMan]

Thanks for all these incredibly exciting pictures Mark. I am deeply envious of them all as henryi, odaesanensis, koreana and some others have probably never been seen in NZ which means they never will be. Nor do we have any named forms of cristata, gracilipes or others you mention here, so far as I know. You are growing them exceptionally well too. It must be a great thrill each year when they flower.

Certainly the Chinese Iris are exciting because they are relatively new to horticulture, and they give the impression of our familiar woodland Iris (I. cristata) but in other colors and guises.  For years I wanted to grow some of the Pacfic Coast woodland Iris (mostly from Oregon and California) like I. innominata, but these are a real challenge here. I would see them in Roy Davidson's garden, in every shade of yellow and other colors, beautifully marked with brown, blue or orange, a kaleidoscope of colors, but these Iris are not for northeastern USA. The Chinese woodland Iris on the other hand are most welcome and amenable to our climate.

Iris cristata forms are very much taken for granted here, hard to get much $$ for them when donated at NARGS chapter meetings and plant sales, as if donating petunias and marigolds .  I suppose we get spoiled with plants that grow so readily in our climate, that we don't give them a second thought (although I do ).  I don't know how true Iris cristata forms come from seed (it's my first try too), but it should be possible to send such ephemeral seed if moist packed; this has worked for Epimedium and Jeffersonia seed

Oh, I was looking through my photos again of Jan Sacks & Marty Schafer's garden, and I found one salvageable photo of the Iris from China I mentioned previously, the one collected by Darrell Probst with near-black stems and bud sheaths, and buds that appear to promise yellow flowers (but Darrell said the flowers open light blue)... so here it is.  I wish I had gone back to photograph it in flower.

[Paul T]

McMark,

Fantastic pics.  Congratulations on the seed.  Mien have never set seed here, and unfortunately I now only grow the straight species as my white form died out a couple of years ago for reasons unknown.  A dainty favourite of mine, and such a shame to have lost them.  Not something I have seen for sale here in Aus either, except for the time I got it maybe 20 years ago.  And your I. henryi and sp novum are absolutely crackers.  Very, very nice.

Thanks for the wonderful pics, both of the flowers, clumps and the seedheads/seeds.  Excellent resource!  

[TheOnionMan]

McMark,

Fantastic pics.  Congratulations on the seed.  Mien have never set seed here, and unfortunately I now only grow the straight species as my white form died out a couple of years ago for reasons unknown.  A dainty favourite of mine, and such a shame to have lost them.  Not something I have seen for sale here in Aus either, except for the time I got it maybe 20 years ago.  And your I. henryi and sp novum are absolutely crackers.  Very, very nice.

Thanks for the wonderful pics, both of the flowers, clumps and the seedheads/seeds.  Excellent resource!  

Thanks Paul. This year has been a learning experience for me, with unlimited time to "muck about" in the garden and play with such things as seed on these beautiful little Iris.  All seed that was available has been sown, but in future years, I see no reason why some ephemeral moist-pack seed could not be shared far and wide

On that note: in the past couple years, when I did catch pods on Iris cristata, I tried the scratch-n-sow in-situ method of sowing seed (had no time for pots and flats), but only got a couple seedlings... my guess is that pods and seeds are very highly attractive to chipmunks and squirrels.  My hope is, sowing in flats, with the wire covering protecting them, will afford the environment and protection they need.

[TheOnionMan]

Today I divided up my clump of Iris cristata alba, and thought it might be a good opportunity for some documentation. 

1   In the upper center is I. cristata alba.  Last year it was a two-fan plant, purchased from Garden Vision Epimedium in May 2009, for $6 US.  Certainly has filled out nicely in just one year.  To the left of it is a similar size clump of I. cristata 'Mountain Girl', and to the right the tiny plants are seedlings.  These plants grow at the base of Stewartia pseudocamellia, a tree with incredibly dense matting surface roots that make underplanting impossible for most plants, but Iris cristata can easily skim the surface bark mulch layer. In this photo, I used a sharp spade and trowel to mix the existing mulch layer into the loosened earth, the surface tree roots chopped out just to give the Iris divisions one season of competition-free growing.

2   I. cristata alba clump uprooted. Don't be fooled by the seemingly dense root ball, most of those roots are Stewartia tree roots!

3   Typical division; usually the fans are paired, sometimes there is a third side fan.  In the center of paired fans is the spent bloom stalk and bracts.  Most roots are from the older joined portion of rhizome, but you can also see a couple new white roots emerging from the two fans, ready to dig in and anchor those fans, later this season to sprout forth with fresh new paired fans advancing the colony. 

4   Close-up of the paired fans and just-emerging anchor roots.

5   Paired fans spaced and ready to plant, with 14 divisions, a 14:1 increase.  

6   Divisions planted and watered in. It's hard to tell, but the rhizomes are left on the surface or just barely covered, but I do carefully place soil/mulch over the new anchor roots.  These divisions will get special attention and watering for the next month.

7   In the center, a 2-year seedling with 5 closely spaced fans that are attached to a developing rhizome, and a 1-year seedling on the right that germinated last summer; it does not have a developed rhizome yet.  I photographed these with the adult-size fans in view, to give an idea of size of these youngsters.

[Maggi Young]

The rhizomes are very slender aren't they?

[TheOnionMan]

The rhizomes are very slender aren't they?

Yes they are, particularly so on alba.

[Lesley Cox]

Your woodlandy soil seems the perfect medium for them Mark. Lots of leaf and twigs and old roots all melded into a rich fruitcake textured compost.

[John85]

I just received some seeds of Iris cristata.They are a very dark brown and Mark  Mc said that they have to be collected in the green.Is there anything I can do to improve germination?

[Rafa]

really nice species, I love them!

[Lesley Cox]

Maybe a good soaking, or even a small scrape of each seed but I wouldn't be too worried, as I've had good germination from very dried up seed of I. cristata. If you have enough, try some as is and some after a soak and see if there's a difference.