Only about half my irises bloomed this year and I want to do better next year. I have a lot of shade in my yard, but most of the plants get at least a half day of sun. Some plants bloomed and others right next to them didn't. I'm going to transplant the non-bloomers this summer and plan to get them in sunnier spots for their rhizomes, not just leaves. Will that help? I've never fertilized--should I be doing that? If so, what kind?

Thanks.

Anne