The wild budgie subsists primarily on a variety of seeds, supplemented by a variety of berries, fruits and other vegetation. Since the bird feeds on the ground, it eats bits of vegetation that have fallen from branches above. Its bill is hooked, which allows it to crack open seed hulls.
In their natural habitat, budgies derive all the nutrition they need, as well as hydration, from the fresh foods they find. However, in captivity the birds are prone to obesity and various nutritional deficiencies if they do not have access to a well-balanced diet.
Many commercial budgie-food mixes contain seeds with much higher carbohydrate and fat content than the seeds the birds eat in the wild. Millet and hemp seeds, which are similar to what a budgie would eat if it were foraging for its own food, offer a higher percentage of protein, .
Some budgie owners tend to overfeed their birds, not realizing that in nature the budgie only eats what it finds.
Budgies also require constant access to fresh water. In their natural habitat they are able to obtain enough water from the fresh seeds and fruits they eat. However, seeds purchased from a store are likely to have dried out considerably, containing relatively little water.