Iresine is a perennial sold as an annual in many garden centers in zone 5. It a useful container plant that will tolerate a variety of conditions from sun to shade. In shade it can get leggy. To get a bushier, wider plant, pinch back the terminal leaves. I have also used it in the garden as a filler plant to cover a bald spot when a perennial has finished. It can get 2-3’ tall with glossy maroon leaves.
It works well in flower arrangements too. As the plants get too tall for my containers, I cut a few stems combine them with some hosta leaves, Coleus and whatever is blooming in the garden for a table decoration. The Iresine and Coleus wil root in a couple of weeks, so they can be a long lasting addition to your arrangements.
At the end of the season, I pot and cut the plant back for a winter house plant. It needs consistent moisture but does not like wet feet.