They quickly turn crispy and look dead when the weather warms in Spokane Valley, but some always come back the next spring (so far).
On a ponderosa pine.
Prunella sometimes looks more pinkish purple than these. This may have more to do with the time of day and my camera's processing than it does actual variation in color. Or maybe it is because some plants are the infraspecies Prunella vulgaris var. lanceolata? I don't know what the differences are.
I do think prunella blooms seem more intensely colored when growing in medium shade rather than light shade. The stems tend to be weak and lean or flop over (procumbent), so I felt lucky to find some that were upright.
Prunella grows along the busy paths I walk. Not in large numbers, but it does seem that they tolerate compacted soil. I was surprised to read that in Montana, they can “invade” lawns.
https://www.flickr.com/photos/plant_diversity/30459994748/in/photolist-NpDref-29rDwam-NpDpPw-29rDv8S-NpDoe7 (Matt Lavin, faculty at Montana State University)
The Burke Herbarium web page describes them as both “Both native and introduced”.