Neal, besides the two Penstemon digitalis cultivars 'Husker Red' and 'Dark Towers', our long-term penstemon survivors are Penstemon hirsutus 'Pygmaeus', P. pinifolius and P. strictus. I find the blue flower colour of P. strictus the most striking. The red flowers of low P. pinifolius are quite small.
Interesting to read that the species, wild type, does not have redness in the leaves.
