I think it might be a good idea to share some of the dumb things we did as we became iris gardeners. Both to give us a good laugh, and to help others learn from our mistakes.
I don't have time to list all of mine, as it would take all day, and no one would want to read all of them
But here's some to start us off:
I mulched my irises that I got the first year I started to buy some in quantity, and I put it on thick! I made sure I watered them every other day that first couple of summers. After all the wild irises that I remember as a kid grew in a bog, so I assumed that all irises needed lots of water. Then I couldn't understand why I had crown mold!
I fertilized with a high nitrogen fertilizer, and wondered why I had such beautiful leaves, but no blooms!