There are both Scottish and Irish versions of this song (sometimes called Green Grass it Grows Bonny). I learned this one from the Dublin born singer Tomás Lynch.
Kate Rusby sang I Wonder What Is Keeping My True Love This Night in 1999 on her album Sleepless and in 2000 at the Folk Festival Sidmouth .
This song, one of unrequited love, I first heard at a women's concert at the Auchtermuchty festival, it was sung by Carol Pryor. I was so moved by the song I felt I had to learn it. I think the song was first heard sung by Ellen Mitchell. I'm not sure where it is from but some of the verses are to be found in many other songs of the same theme.
Ellen Mitchell of Glasgow sang The Rue and the Thyme in May 2008 at the Fife Traditional Singing Festival, Collessie, Fife. This recording was released a year later on the CD Grand to Be a Working Man (Old Songs & Bothy Ballads Vol. 5).
Josienne Clarke sang I Wonder What's Keeping My True Love Tonight in 2014 on her and Ben Walker's CD Nothing Can Bring Back the Hour .
I wonder what is keeping you out of my sight.
And yet you stay from me this night I'm not sure.
Oh love, are you coming your own cause to advance?
Or yet are you waiting a far far better chance?
Are you coming to tell me you've a new love in store?
Are you coming to tell me you love me no more?
For yet I'm a-waiting a far far better chance.
I'm coming to tell you I love you no more.
And I can love the old love till the new love comes on.
And when I'm not with you I'll love whom I please.
For I can't love a love with one too many sweethearts.
The fonder I loved you the falser you'd prove.
I'm sorry and tormented for the love of my false dear.
That descends in the evening, goes away with the dawn.
I wonder what is keeping him out of my sight.
And stays from me this night I'm not sure.
Oh love, are you coming your cause to advance?
Or yet are you waiting for a far far better chance?
Or are you coming for to tell me you love me no more?
I can love the old love till the new love comes on.
For when I'm not with you I'll love whom I please.
For I can't love a man with too many sweethearts.
The stronger I loved you the falser you grew.
I'm sorry and tormented for the love of my dear.
That's there in the evening and away with the dawn.
But a thorn pricked my finger and I left it behind.
Oh ye'll pull the red rose, I will pull the rue an' thyme.
Ah, but now I must tell him that it's time for tae rue.
Oh ye'll pull the red rose and I'll pull the thyme.
Since ye've been unfaithfu', then I'll be unkind.
And here's a health tae the laddie that is maist on my mind.
I can love a new love when my love is gone.
Ah, but noo his back is tae me, I can love who I please.