My first memory of The Ash Grove is hearing the beautiful Elizabeth Bennett sing (in the BBC's version of Jane Austen's Pride and Prejudice (BBC, 1980) and accompany herself on the pianoforte as an aloof Mr. Darcy slowly circles the room, really seeing her for the first time. (It is hard to choose, but this may be my favorite of all the Jane Austen movies. It has a very good-humored feeling about it.)
Though I can't show you a video clip of Pride and Prejudice, here is a nicely sung version by Nana Mouskouri:
Ever since seeing Elizabeth Bennett singing the Ash Grove, I have loved this song. It is not very difficult, but it has a few features that make it one of those songs that teach vocalists how to sing better.
For example, on page 2, the second line has a bit of a rallentando, and the temptation is to drop the energy of the voice just when it needs to be carrying through, even surging, at "the joy of my heart..." Also, there are long phrases in the first half of the song, where beginning singers will want to take lots of breaths. Don't let them! Teach them what "breathing for singing" means, by encouraging them to make their air last all the way to "meander," and again until after "rove."