How to start a small rock garden for growing Penstemon?

Submitted by sf2bos2prov on Wed, 10/02/2019 - 12:51

Here in Boston, this was a good year learning about Penstemon and I've grown some species in pots filled with various gravel and grit, thanks to help I received here.  Now I'm ready to go a step further.  I have a small sunny area of about 6 or 8 feet long and 1 foot wide at the front of a flower bed, in which I'd like to create a small rock garden to grow some of the low-growing Penstemon species, maybe even some of the blue-flowering ones.  But I have no idea how to create a small rock garden.  Can someone point me in a good direction?  Are there resources for doing this on the NARGS website, or articles/books elsewhere you could refer me to, or just offer a few pointers?  Thanks.