I’d tackle it in stages, starting with the least aggressive method and only adding more elbow grease if the stain doesn’t budge. First, empty the can, remove the liner, scrape off any loose food, gum, or sticky residue with a plastic scraper, and give it a quick rinse with hot water. For most greasy urban grime, hot water plus a mild dish soap is surprisingly effective. Add a few drops of soap to a bucket of hot water, pour or sponge it over the stain, let it sit for five to ten minutes, then scrub with a stiff nylon brush. Work from the rim down so dirty water doesn’t run over areas you’ve already cleaned.
For stubborn stains, make a baking soda paste by mixing baking soda with just enough water to form a thick paste, and add a drop of mild dish soap if the area is greasy. Spread it over the stain, let it dwell for 10 to 15 minutes, then scrub in small circles and rinse well. Baking soda gives you gentle abrasion without scratching most plastic or metal bins. If the stain looks like mineral buildup or the can still smells sour, spray white vinegar on that area separately, let it sit for a few minutes, and scrub again. Don’t mix vinegar and baking soda together in the same container for cleaning, because they neutralize each other; use them one after the other instead.
For sticky adhesive, gum, or scuff marks, steam is a great low-chemical option. Hold a steam cleaner or a hot, damp microfiber cloth against the residue for a minute to soften it, then lift it with a plastic scraper. Repeat rather than digging at it with metal tools, which can gouge the surface and create places for dirt to collect. If you have a pressure washer, use the lowest effective pressure and keep the spray away from wheels, hinges, seals, and any electrical or mechanical parts. A stiff brush and a good rinse are often enough for the inside.
After cleaning, rinse thoroughly and let the can dry in the sun with the lid open. To keep stains from coming back, use liners, rinse the can weekly, and sprinkle a little baking soda in the bottom to absorb odors. Wear gloves and eye protection, test any new method on a hidden spot first, and never mix cleaners such as vinegar and bleach. This approach takes a little patience, but it handles most stubborn trash can stains without harsh chemicals.