Sorry, didn't notice you said chords, not lyrics. I'm not very talented at making the chords appear over the words in HTML so here's the best I can offer (Triona sings it in this key on the live Bothy Band album; if you need it in a different key just holler):

(C)I wish my (F)love was a (C)red, red rose
(C)Growing (G)in yon (F)garden (C)fair
(C)And me to be the (F)garden- (C)er, of her I would take (G)care
(C)There's not a month through- (F)out the (C)year, but my love I would re- (G)new
(G)I'd (C)garnish her with (G)flowers fine
(G)Sweet William, (F)thyme and (C)rue.

Good luck making out my system... also note that if it's the Mick Hanley version, he does the melody of the first line a bit differently, so the chords are a bit different, to wit
(C)I wish my love was a (G)red, red rose

It's a bit simpler and actually I like his better. Margaret