My pond is just a submerged plastic prefabricated tub. I have flat stones all the way around it. There isn't really a good place to plant next to the pond, so I want to try growing them in a pot in the pond. Just not sure what to do with the pot in the winter.

Use your imagination, plant the iris behind the pond close to the flat stones

and arrange rocks around the iris in the back...I'll see if I have a video of our pond with the irises in bloom.

A sorry, I can't find any videos with the Siberian iris in bloom.

ill post this one, study it...lots of stuff planted around the pond. Some things in the ground and some things planted in pots and the pots are buried at ground level.

My wife got some potting medium for water plants from Amazon and put the iris of some sort in this stuff in a container in her plastic lined pool. They bloomed briefly but profusely the second year.

I know that invasive yellow flag irises can be grown in water. They are known to choke out streams by inhabiting water ways. So my guess is that Siberian irises which thrive next to ponds could also grow in pots in the water. You could try it and see how it goes, since these irises are "extra" plants.

They can and will jump out of the pot you put in the water. I have had it happen twice. ALL of that family of iris. Plant on outside of pond some way. They roots get out the bottom and you will be fighting them from then on . Only takes a very small piece of root for it to be back. And it will over winter both in and out of water.