Propgating Pacific Coast iris

Rodger Whitlock
Sat, 01 Oct 2011 16:44:56 PDT
My garden is in the midst of a major upheaval as the municipality is 
reconstructing a superannuated wood stave storm sewer that runs across it. 
Since last fall, life has been a continual round of lifting plants that are in 
the way.

Among the treasures I particularly hoped to save was a large clump of an 
exceptionally beautiful Pacific coast iris, with flowers of a nearly white, 
silvery blue. Ten days ago,I was successful in digging the clump up and have 
planted it in a large bulb crate for the duration. But of course, any amount of 
the clump broke off, leaving me with a mass of small divisions.

I have treated these much as you would cuttings of other plants. They were cut 
up into small pieces of rhizome, each with a single growing point, and the 
leaves cut back to only an inch or two, then dibbled into a flat of soil, the 
whole watered well afterwards.

A week later many of these tiny divisions are already showing signs of active 
growth, as evidenced by the growth of new foliage. It's too early to be sure of 
success, but early indications are that a good many will survive.

The Pacific coast irises mostly hale from summer-dry climates, and new growth 
is initiated in the fall when temperatures fall and a little rain starts to 
come down. As with many other plants, division when new growth starts is the 
key to success. Divisions of other PC irises taken in the past in early summer 
just after flowering were very slow to establish.

PS: during The Lifting of the Clump, the original label turned up. It's Iris 
thompsonii (or so the label says), sown in 1992.

Rodger Whitlock
Victoria, British Columbia, Canada

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