I started a few of these plants about four years ago and like the other pyrenaicum varieties I have, they are spreading generously or dangerously around the garden. I have them in the ground in the orchard bed and the memory garden, and in pots on the driveway, as well. The plant can grow astoundingly quickly and large and produce an enormous amount of flowers. Still, it never reaches showy status. It tops out somewhere between pretty and interesting.
My 2020 plans for these plants will be to root out any extras to slow their spread and enjoy the flowers as they grow and bloom. They take absolutely no care except average water, so no need to feed them or anything special.