The diet of a wild budgie?

[ThoseTwoKeets]

I have two parakeets (budgies) and I want to know what the most natural diet is. I know it's supposed to be fruits, vegetables, and seeds, but in the wild what would a parakeet eat?

I would think they'd eat seeds and grass, along with some sand for grit, though I'm probably incorrect.

 

[Doublete]

I don't know about the grit but I thought parrots (budgies included) don't need grit and it actually harms them.