It's after good friday should be ok to plant but watch the weather and cover any young plant if it looks like frost.Plant the bulbs when they come in fall is the right time.All most any will grow here some will do better than others.

In zone 7 in Georgia the advice is to plant after April 15 - that is usually past our last frost. Maybe Mississippi State's ag school posts frost dates on their web site. If zone 7 in Mississippi is anything like zone 7 in Georgia - my Mom lives in Memphis and ya'll seem to be a little colder in winter than we are - Siberian irises are indestructible. You'll have to wait for someone else to answer about bearded iris or some of the other types - Louisianna, Japanese. Hope this helps out a little and hope you have a good time gardening.