Truthfully, I don't know a whole lot about Penstemons, but based on the descriptions in my Sunset book (unfortunately no pix) I'm guessing it's either a P. cobaea or a hybrid, possibly one of the Mexicali hybrids. But good grief there are a lot of them. Seems like I always think about IDing it in the winter when the foliage is ragged.
I can rule out many because they bloom only in the blue/violet range. Others have grey leaves—nope. The dark green basal leaves turn purple-ish some winters. Growth habit is open and floppy, not compact.
