In general, it does take two bloom seasons before an iris performs to its maximum in a new garden. That's why AIS conventions/regionals call for guest two and three years in advance of the convention.

Sometimes, really large rhizomes bloom the first year, but the stalk may not be the registered height.

I got a few rhizomes from a neighbor and planted them the day they were dug and they are blooming as if they had never been moved.

Soil, climate, weather, culture all figure into first year bloom after transplant.

Walter Moores

I've found I get little bloom the first season after planting new rhizomes (or dividing old ones) - generally one out of three. The third year is the magic one for me. For instance I moved in summer 2001 and replanted all my irises in their new home, then added tons of new varieties in 2002. 2003 was pretty good for blooms, but 2004 was unbelieveable. The garden was overflowing with irises. Of course they all had to be dug that year too s the clumps were enormous. I think you'll see lots of flowers this year and even more next.

Mike

Last year I divided some rhizomes and got nothing but foliage. But just last week I got my first bloom, and now they are thriving and are absolutely BEAUTIFUL with 3 or 4 blooms on each stalk. I would give it a few more weeks, since you're in zone 5...

I'm sure they will turn out beautiful!!