What an excellent and exciting idea. I tend to use this as a plant in areas with poor soil, or naturized garden look. It prefers acidic soil, and if cared for by you might grow to 3 or 4 feet. Here is a link for propagating it, not that you want to do that, but it talks about its needs and idiosyncrasies, see Propagating Sweet Fern. Plus there is a nice picture at the bottom of the plants placed around a tree.
Sweetfern is an excellent choice for the more barren or acidic areas of a garden – those spots where nothing else seems to do well. It will thrive in acidic soils, forms a nice dense thicket, and stays within reasonable size limits, so no pruning is needed. And best of all, you won’t have to hike to a high, dry hilltop to experience sweetfern’s wonderful fragrance.
It can be left alone to colonize. Also a good plant for stabilizing slopes or embankments.
I think if you tend it a little you could get it to grow fast and large, but check on how much fertilizer it prefers. If you mulched it with oak leaves or pine needles it might do well too.