Ah, SO! I just found the same typo in the Digital Tradition version. It credits the Joan Baez song book, which probably explains it. In version 2 in the DT (similar, but with some differences), recorded by the Ian Campbell Folk Group, that verse reads

Down in yonder garden gay
Love, where we used to walk,
The sweetest flower that ever I saw
Is withered to a stalk.

"Garden gay" or "grove." Makes much more sense than holding hands and strolling in a "grave."

Don Firth