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How to Start a Wild Iris From Seeds
By Meg Butler
Wild iris grown from seed must grow for at least two years before it will flower.
Starting wild iris from seed is a simple task, but it requires patience. Wild iris seed is sown in September and must spend the winter underground before it germinates in spring. Once wild iris germinates, it must grow for two to four seasons before the plant is mature enough to flower. When the wild iris does flower, however, it will produce three to four flowers per stalk for most of the month of June.

Read more: How to Start a Wild Iris From Seeds : eHow http://www.ehow.com/how_7339031_start-wild-iris-seeds.html#ixzz2TYgip6GF
Water your iris seeds and surrounding soil frequently enough to keep the seeds and soil constantly moist, but not soaking wet, from the time of planting through sprouting in the spring. Local rainfall and weather, planting location and soil texture will impact how frequently you need to water. Warmer climates with little rainfall and fast-draining soil will require more frequent, even daily watering. Cooler, rainy or humid climates with humus-rich or clay soils will require less frequent watering.
Moisten the seeds and soil slowly with a very gentle mist so as not to displace the seeds or disturb nascent roots. A hose attachment set on a mist or light rain setting will help to keep the seeds and soil in place.
Set automatic commercial mist irrigation systems to provide your iris seeds with a regimen of 10 seconds of active misting during each 15 minutes of sunlight or artificial daylight hours.

Water iris is a pretty general term, but most iris seed will respond best to a warm moist period, followed by a moist chill, will then germinate when brought to warmer but still cool. If your climate doesn't provide those conditions, you may have to sow indoors, use your refrigerator (not freezer) for the chill, and cross your fingers on having a coolish room for the last stage of germination. How the plants themselves will fare in your temps long term, I can't offer a guess :)

Iris in general and holds true for almost all types: Impervious seed coats. Shake in dry sharp sand or nick carefully with a file. You may want to soak overnight after nicking. All periods must be moist, with seeds in damp not soggy medium. In order - 70F for 4 weeks, move to 40F for 6 weeks, bring back to approximately 50-55F for germination which may be staggered over many weeks time.