I am going to try what I do with hostas and see if it works. The only ones that heaved were the ones in the raised bed.

I have a stack of red bricks from a project done on the house. I use them to circle around the hosta and I mulch with leaves. I have never had my hostas winter heave since I did that.

We have freezes and always have a winter thaw that kill any plant that have a tendency to heave in our freeze and thaw weather.

Heuchera heave much more then Hosta. In the same garden that the Heuchera heave the Hosta are all fine.. The bricks should help, but I find that mulch does not really do anything but make it harder to see if the pant heaved.