Dividing Irises – Part 2

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A little more than a month ago (October 14) I dug up a few Pacific Coast irises from the woodland garden to transplant to a new location – one that won’t make such an appealing doggie bed for Milo. I started in October because I could see the irises were coming out of dormancy. After all, this fall has been anomalously cool and wet. It seemed a bit early, but I went ahead with it. Well maybe it was a bit early. As you can see below, the blades have died back and I cut them off. The rhizomes may be fine and ready to re-leaf, I am waiting to see. I thought that it was important to transplant when the white nubbins growing from the rhizomes were about 1/2 inch long. That is not what I have been reading so it will be interesting to see whether the ones I transplanted on Sunday do better.

One month after planting, and yes I did keep them moist, they have died back. I still think they will be fine and will keep checking for new growth from the rhizomes.

There has been much discussion on the web about dividing irises. If you are on Facebook, check out the photos uploaded by Bob Sussman of Matilija Nursery (and be sure to “Like” this great page). Bob has graciously allowed me to copy the pictures for posting here for those not on Facebook. There is also a nice article on dividing irises on the Matilija Nursery website. Another excellent resource on irises is the Society for Pacific Coast Native Iris (and guess who is president… yes, the same Bob Sussman of Matilija Nursery).

Pacific coast irises in fall-big and ready to divided. (Matilija Nursery)
Pacific coast iris divisions-you can see the natural “breaks”. (Matilija Nursery)
Pacific coast irises planted to containers to “root out”. They can also be planted to your garden. (Matilija Nursery)

 One of the things I noticed when comparing these pictures with mine is that the roots of Matilija Nursery’s irises are thicker and whiter than the roots of the ones I transplanted in October. Probably, this is partly due to the fact Bob recommends washing the roots and dipping them into a dilute bleach solution, but I also think it is another indication of the fact that I jumped the gun on these irises – took them too early, before the feeder roots had started to grow. But who knows, I’m not giving up, just yet, on my early transplants.

On Sunday, plant sales over, I turned my attention to my own garden and the remaining irises that I wanted to transplant. Dug them out, divided and planted them. One of the tips everyone seems to agree upon is the need to plant them immediately. Pacific Coast irises (beardless irises) are more sensitive to transplanting than bearded irises and really do not do well if their roots, exposed to air, dry out. Luckily the weather was cool and moist.

Gently lifting out the irises.
Set in a wheel barrel, ready for the trip to other garden beds, awaiting their arrival. (Notice Milo in the background wondering what I am doing to his bed.)
Irises are gone. I think I will extend the flagstones so there is more walkable space.
One of the many new divided irises planted in an area that used to be filled with a white fly infested xylosma (glad to be rid of that!).
New planting of irises on the side of the house. Not the neatest look, but we’ll see how they do!

To put this whole project into perspective, here are some pictures of these irises from their beginnings in my garden.

Woodland garden in 2002 before the lawn is removed (left), and the first small planting of Iris douglasiana ‘Canyon Snow’ and a Pacific Coast Hybrid, 4/11/2004, (right). The orange flower on the far right is a clivia left over from the previous owners.
Irises in front center in July 2005.
Closeup of Iris douglasiana ‘Canyon Snow’. No wonder we plant these!
Irises in late April 2006. Very pretty!
February 2009, irises emerging from dormant period with upright blades.
Milo, at age 13 1/2, is looking for a cool place to lie down on a hot summer day, July 12, 2011. Next summer he will have to use the carex instead.

When I started this post I was going to discuss my insecurity about being messy (which I hint at above, in the description of the picture of the new iris bed). Yes, I am a bit of a mess and after seeing how my friend Nancy planted the irises that I shared with her, I was all set to fess up, looking for kind words like, “Oh, you are not a mess. Your garden is beautiful..” Well, you can keep your kind words (if you have any), but enjoy these pictures of Nancy’s new transplants.

Isn’t this amazing? Look at how neat this garden is!
I love the rocks, the trunk of the Ceanothus, and the irises, dressed with a mulch of light pebbles.
And if all of that is not enough, add a gorgeous cat posing in this garden of Eden. Well done, Nancy!

Time to wrap it up with a picture of the irises naturalized in the riparian mesa area at Rancho Santa Ana Botanic Garden in Claremont. People often ask me when is the best time to visit Rancho. It is always beautiful, and my favorite part of the garden is the wild community area in the back 50 acres. Still, if you could only visit once (and that would be a shame!) then I would recommend coming in mid-April for the irises on the mesa, it is magical!

Irises with wildflowers at Rancho Santa Ana Botanic Garden on April 17, 2006.

2 thoughts on “Dividing Irises – Part 2

  1. Pamela

    Great post! Very thorough. I forwarded it to a friend in Atascadero who wants to plant iris under her oak trees.(Theodore Payne Foundation is advising her on which iris to plant for that kind of location.) So thanks!

  2. Glad you liked it. Now we wait to see how my transplants do. Hope your friend has lots of luck with these beautiful plants.

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