Posted: 05/08/2013 at 13:00
First the seeds, when the pods splits and you can see ornage/brown seeds then they are ripe. Sow fresh and leave exposed to the weather over winter. They then should germinate in Spring. They take about three years minimum to reach flowering size, possible longer.
If the Iris have rhizomes then they are easy to split. Now is the time to do it.
If they have a more fibrous root (Iris sibirica has) then you can split the clump in early Autumn, but not into small pieces. For some reason I. sibirica does not like being divided into small pieces.
If they are Californian Hybrid Iris then they do onot like being disturbed at all.