I've always dreamed of having an iris walk. I have yet to put one in, but am still giving the idea much consideration. Irises are sold with labels such as "Late", "Mid Late", "Mid", "Mid Early", "Early", or "Extra Early". It is advisable to get several type of irises with different bloom times so that your bloom time is extended. Of course, now there are also re-blooming irises.
So, putting in an iris walk has more consideration than just what color (or colors) of iris you prefer. And, of course, there are bearded irises, siberian irises, louisiana irises, dutch irises - well, you get the picture. There's a lot of irises to choose from! Designing an iris walk would take quite a bit of research and planning.
Still, I hope one day to do just that.
I have a few different irises in my garden, but the majority of them are "Extra Early".
These are iris albicans, some call them "cemetery irises". These irises in my garden came from the secret garden in the woods close by my house. They are easily transplanted, and I just dug these up while they were in bloom, and put them gently in my garden. They should be planted shallowly, almost on the top of the ground.
These irises grow in zones 4 through 9, and are usually passed from gardener to gardener. The buds have a slightly silver sheen to them, opening to a pure white. In my garden, I love how they draw attention to the new red leaves of the 'Mrs Dudley Cross' rose.
When/if I ever create my own iris walk, I will definitely include these in the mix. They are one of the most reliable early spring blooms in my garden. I can't imagine my garden without them!