Joe will be appearing at the Calgary Folk Festival, which runs from July 22 to July 25. The official schedule has JH performing at 4:30pm alongside The Swell Season and Robin Holcomb. However, High Road Touring lists him for July 25 at 10:30am.
Probably trust the official schedule – I'll try to verify.
(Thanks to regular reader Stephane for the tip!)
UPDATE: It appears that your best bet is Friday, July 23, on the Main Stage at 6:55pm.