My dwarf hairgrass arrived in a rather brown and somewhat slimy condition... even some of its roots were not so lovely looking. (there was a label on the shipping container that said, "DO NOT FREEZE"... so maybe it had frozen since the night temperatures were quite low.)
However, the video I had watched a couple times on planting (the video with no talking because I don't think the man speaks English, but with great typed directions) said to trim the plants way down, and to also trim the roots.
So, I trimmed. I planted tufts that were about a half inch high... using tweezers. They are all looking really good, bright green. I'm thinking they must be making lovely roots in the substrate. They look as if they must be.
One of the tufts was pearling today... just minimally, but still ... little bubbles of oxygen.