I just thought I'd share with you one of the treats I give my birds. I've named the treat "Kale Stick" and all it is is the stem of a kale leaf with all the leaf part ripped off. I also do it with Rocket.
I started giving it to my canary and it lasts him all day. As well as eatting it it's also a preening toy because of all the fibres in the stem. Definatly reduces bordom for your birds if you're away.
After trying to get Charlie to eat his vegetables without any luck I decided I'd hang a "Kale Stick" from the roof of his cage with a peg right near his favourite perch. It didnt take long for him to test it out and now I finally have him eatting it. I believe I can start hanging other vegetables the same way and hopefully he'll try them.
Here is a picture of Charlie with his "Kale Stick"