Would love to start a discussion on planting under arborvitae where masses of feeder roots are a problem, and would appreciate suggestions on best plants to try.

On a small lot, one fence line has 40 feet of large, well-established arborvitae. It was a wasteland underneath until I added soil 7 years ago and began experimenting with plants.

My experience is that any plant that is bare root or bulb-based is less successful. Hostas sort of survive, but they don't thrive. I've tried astilbe, heuchera, unsuccessfully, and when I dig them up in the fall, the roots are tightly wrapped/strangled in the arborvitae fibrous roots.

What does absolutely thrive in the shadiest sections are hellebores/lenten roses. Gorgeous flowers in the early spring. I understand that hellebores have deep roots and, so, have concluded that they are rooting down below the feeder roots of the trees. Lilies of the valley and, of course, vincas, work (vincas seem controllable, here). And, last year, I planted some liriopes that seem to be taking. For color, we plant a few annuals such as impatiens and begonias on the (somewhat) sunnier edges.

Would love to have plants such as siberian bugloss, but other commenters say they don't work in areas with these aggressive feeder roots. A dwarf japanese maple is on my wish list, but I understand these have shallow root systems. Could it work in a buried container?

This year, I'm burying some pots in the garden and trying hostas in them, to see if that isolates them from the tree roots.

Any other ideas? Thank you.