I've been growing this little linear-leaf Penstemon for a few years in a trough, purchased from a New England grower of rock plants. It's not very showy, a few stems with a few tubby violet flowers at a time, never many flowers at once but stretched out over a few weeks. The stems reach about 8" tall. The plant does not match photos I've seen on the USDA site, which I include links for comparison... the leaves on my plant much too narrow compared to USDA photos (see below), and as well, the USDA photos shows flowers spaced much more densely along the stem in congested manner. Any have an idea about what Penstemon species is living in my trough?