Jack,
Jim reminded me about Bronson. There are 2 versions in Bronson with similar first verse. No 28 from Ulster and No 46 from Boston, Mass. Both could have easily derived from a Scottish version

28
As I went over Bonny Moor Hill, Every rose grows bonny in time
I met a wee lass and they ca'd her Nell, She was longing to be a sweet lover of mine.

from Coleraine.

46
As I walked out in yonder dell, Let every rose grow merry in time
I met a fair damsel, her name it was Nell, I said 'Will you be a true lover of mine?' 1894 (Boston)

Walker
As I gaed up to yonder hill, Saffron, sage, rue, myrrh and thyme,
I met my mistress, her name it was Nell, And lass gin ye be a true lover of mine?