Yes — beets are safe and nutritious, and the leafy beet greens are excellent too. Expect dramatically pink droppings.
Keeper's noteRaw grated or cooked. The vivid betalain pigment turns droppings (and beaks) bright pink/red — completely normal and a common cause of needless panic.
Why beets is good for parrots
Beetroot is non-toxic and brings folate, fiber, and antioxidants, while the greens are vitamin-rich leafy fare. Beets do contain some oxalates, so they're a rotation vegetable rather than a daily one, but they're a colorful, healthy addition.