I have the hygro in several tanks. I have also taken it with me in past years to fish events to sell. it all came from a single small piece msjinkzd put into the bag of red cherry shrimp. For those who do not know this, shrimp need to be able to grab and hold onto things. In a plastic bag this is not possible. So when folks ship shrimp they will add a piece of a plant or anything similar the shrimp can grab onto along the way.
I literally have populated several good sized tanks over the years from a single 3 or 4 inch stem which did have a couple of leaves on it.. And it grows like crazy.
I will post a pic in the next few days. Life now is a bit crazy so little seems to be happening on schedule. However, I can tell folks that of the 4 stems planted, 3 show new leaf growth and did so in a matter of days. The 4th stem is barely an inch tall and so far no signs of leaves. It is also in the new pot I used in a hurry for the stems. This was dry gravel and I added no ferts to it. The only ferts are the ones in the water itself and that tank is a jungle which gets a good dosing once a week in the water. The tanks with the single stem in the gravel has grown new faster. But that tank has both water table and substrate ferts in it.