Note bending is done with draws. You kind of do the shorter notes with exhales, I never really 'blew' them, I just let the air out of my lungs with a bit of force through the mouth. Playing songs is different from scales. It's kind of like working out upstrokes and downstrokes with a pick, they sound different
You can bend notes blowing too. As I said earlier in the thread, bending notes is about the only thing I learned on harp, showed how by a buddy who is an exceptional harp player. Bending when drawing in, you are bending the note down. Bending when blowing out, you are bending the note up.
I'll try to explain "how" to do (this'll probably be funny).
Ok, to bend a note down (draw), you drop the floor of you mouth while simultaneously moving the base of your tongue "back" & "down" towards your throat.
To bend a note up (blow) you do the opposite of the above. Raise the floor of your mouth towards the top or roof of your mouth while simultaneously moving the base of your tongue forward towards your mouth (basically make the cavity inside your mouth small & all crammed up towards the harp).
This is basically how it was explained to me, after he had first showed me how to use either my tongue tip or small lip aperture to play single notes. Didn't take long to learn to bend notes both ways, & I'm no harp player. Cheers
Edit:
I should have mentioned earlier (though I think most would realise anyway) that to effect the bend in either direction, you start playing the note normally before doing the "mouth manipulations" to bend the note. Cheers