Is Mat Penstemon deer resistant?

Nothing here is upright. Prostrate stems with ascending tips run out into a dense mat four to six inches high, studded with small blue-violet flowers from May into August. Deer leave it be.

It gets lost rather than killed. At that height it disappears under leaf litter, under mulch, under any neighbor that flops in July, and a wet fall's worth of debris lying on the mat rots it from beneath. Gravel, a rock ledge, a gritty trough — somewhere water runs off and leaves blow away — is where it actually survives.

Full sun, thin well-drained soil, no compost and no feed at any point. In a mixed bed it simply vanishes; on top of a dry wall or in the gaps between paving it does the one thing it is good at.