you should probably with till the stem leading to the seed pod hardens and stops carying water and nutrients to the seed pod naturally before cutting off its suply, also yellow flag Iris is invasive in many places isn't it?

Hola- I let the seeds ripen before I take them off the plants. They always sprout for me. I have a few marsh mg, and some bog irises too. Luis

Gracias, Luis.

Que Dios te bendiga.

S

I would wait until the flower pods dry and split open, personally. Let Mother Nature do the work for you!

Yes, yellow flag iris is very invasive. If you deadhead it faithfully, it shouldn't be a problem. The seeds float, and can float "downstream", which is why they're a problem. I just dug all my yellow flag up and put them on the compost pile.

I hear some people wrap the seeds in a damp paper towel and keep them in their frig. Or they keep the seeds in a cup while storing them in a cool dark place to allow them to dry. Then freeze them and plant them in pots in late Fall. And keep the soil moist.
Does anyone know how deep to plant the seeds?