The short answer for a Bourke's parakeet
Change the liner under a Bourke's parakeet's cage floor every day or every second day, wash its food and water dishes daily, and give the whole cage, floor area especially, a proper wash once a week. A Bourke's produces far less mess than a big parrot, and owners sometimes let that small output stretch the routine too far. The catch is where this bird lives within its cage. Bourke's are grass parakeets that naturally forage walking on the ground, and a caged bird does the same across the cage bottom, picking through scattered seed exactly where droppings also land.
Why the cage floor is the whole issue
Most cage birds live on perches and only the tray below gets dirty. A Bourke's parakeet commutes between perch and floor all day, hulling seed on the ground, sipping from low dishes and sometimes resting there at dusk, its most active period. That means bacteria building up on a floor grate or in an unchanged liner is not downstairs storage; it is in the bird's feeding area. It also means the daily liner change doubles as your health check, since Bourke's droppings are small and a fresh sheet makes changes in amount or consistency visible that a week's accumulation would hide completely.
A weekly rhythm matched to a quiet, crepuscular bird
Do the daily jobs, liner and dishes, whenever suits you, but time the weekly full wash for the middle of the day, when Bourke's naturally rest and are least disturbed by being moved to a spare cage. Scrub the floor grate or solid floor first and longest, then bars, perches and dish holders, rinse everything thoroughly and dry it before the bird goes back, because a damp floor invites exactly the growth you are cleaning to prevent. Twice a month, wash seed and water dishes more deeply, check the corners where husks wedge, and inspect any ground-level toy or flat perch for soiling that wiping missed. Replace worn wooden perches rather than endlessly scrubbing them.
Cage or aviary, the floor rule is the same
Bourke's parakeets are also kept in planted aviaries, where there is no liner to change; the floor-first logic still holds, it just changes tools. Rake and spot-clean the aviary floor daily, keep feeding stations on washable trays or slabs you can scrub weekly, and never let seed husks build into a damp mat in corners, because these birds will walk out and forage through exactly that mat. Indoors or out, a Bourke's earns its living at ground level, and its keeper's cleaning schedule has to be built at that level too.
Keeping cleaning gentle for a gentle species
Bourke's parakeets are placid and easily startled by fast, looming movements, so clean around them slowly and speak as you work if they stay in the cage during the daily liner swap, or move them calmly for the weekly wash. Use hot water and plain washing-up liquid or a bird-safe disinfectant, rinse until nothing slippery remains, and never use scented sprays near this or any bird. If you notice droppings turning watery, a bird spending unusual time fluffed on the floor, or husks untouched across a morning, treat that as a prompt for an avian veterinarian rather than a cue to simply clean harder. KinsLe Care Teams can hold the liner changes, daily dish washing and midday weekly wash as assigned duties marked done with a timestamp, keeping your Bourke's parakeet's floor-level home consistently clean.