Creeping ground mint habits

I have an area that I wanted some groundcover, and our local native nursery suggested either creeping ground mint or foam flower. The nursery had little seedings of each, and they looked nearly identical. My solution, of course, was to buy 4 of each, plant both, and see which I liked better when they grew up. :)

The tiarella is a huge success. All plants are about 1 foot around, not including the long tendrils they are sending out in all directions. I'm expecting them to cover most of the area by next year.

The ground mint is rather a bust. Each plant has a single creeping vine under a foot long, and that's it. They're kinda puny looking. Is this normal, or should I move them to a different location? The current location is mostly shade and stays fairly moist. They look healthy, just very small.

I'm not familiar with creeping ground mint. Do you have the latin name for it? Out my way we use that name for a nasty weed. Can't believe it would be sold, so it must be something else. Maybe post a pic?

The tag says "Meehania cordata".

Ah. Not a speck of shade here so that's why I didn't know it. I'm sorry I can't help, as I don't have any experience with it. Plant files entry says it loves shade. And there is a phrase for some of the prairie natives, "first year it sleeps, second year it creeps, third year it leaps". So if it looks healthy...

There are a couple of other native plant forums beyond here if you're still looking for more info.