If you fertilize them be sure it is Low nitrogen! before flowering time works best. I do not fertilize mine just add bone meal now and then. Good luck.

As Aqua said --- low nitrogen, as in bulb food and others. Look for the 3 numbers on the pkg. 5-8-8 or 4-6-8 etc.

Recently I've read people touting 10-10-10 but I wouldn't.

You can feed a month after flowering. And in the spring about 6 weeks before bloom time.

Here's a link to Schreiner's good information.

Here is a link that might be useful: http://www.schreinersgardens.com/about_iris.shtml

Thanks! I used Espoma Bulb Tone, which is 3-5-3. Thanks for the warnings on nitrogen. The link was very informative! I am trying to remember if my rhizomes are still uncovered. I planted them that way, but I wonder if they settled. If so, should I uncover them some, or let them be? Thanks again!

Absolutely! Covering the rhizomes causes them to rot. They like it dry most of the time. I water once a week in the peak of Summer. One a monthe Spring and Fall.

Ok...I will uncover them tomorrow. I hope the silly things stay buried this time. (They are just barely under the surface.) thanks!