I know you've done it too, bought a plant with NO idea whatsoever WHERE you are going to put it. I just ordered some Siberian Irises. All my Irises are the big Bearded Irises. At my husband's last house I had planted some blue Caesar's Brother Siberian Irises and he loved them.
He happened to casually mention them again.... and since I can't find them at any of the local greenhouses, I ordered some bare root bulbs. Then, I ordered a batch of mixed Siberian Irises for myself. And I have NO idea where I'm going to put them. But that's OK, they can live in pots along with the Windflower and Black Eyed Susan volunteers that I dug up and couldn't kill. Really it's not a bad plan. I've saved a couple of flats of the big one gallon pots my local greenhouse uses, so now I have a nice tidy collection of the next generation of perennials potted up and ready for our future flower beds.
Siberian Irises are beautiful, and while they don't have the huge impressive blooms of the Bearded Iris, they also don't droop all over the place and require supports. Since I had such a profusion of iris blooms this spring, I quickly ran out of stem supports. The Siberian Irises have longer narrower leaves, and look grassy or rush-like. They love damp soil (which I don't have) but are so determined they will thrive just about anywhere and require frequent dividing if you expect them to stay in their designated place. The best situation for them is their own bed on the edge of the lawn where they can provide a natural looking background. With that in mind.... I still have NO idea where I'm going to put them.