As I learned it. I'm not sure where, but I think it was out of A Treasury of Folk Songs compiled by John and Sylvia Kolb, a Bantam paperback I bought off a drugstore rack for 35¢ back in 1952. A great starter kit! No problem with anomalies in that version.

They buried her by the old church tower;
They buried him beside her
And out of his grave grew a red red rose
And out of hers a green briar.

They climbed and they climbed up the old church tower
'Til they couldn't climb any higher;
There they twined and they tied a true lovers' knot,
The red rose 'round the green briar.

[The red rose grew out of Sweet William's grave because his love was true. The briar grew out of Barbara's grave because she had "issues."]

Don Firth