That's an excellent and very practical question! Maintenance is a major factor in choosing the right bench, and the good news is that most modern benches are designed with easy cleaning in mind. The ease of cleaning primarily depends on the material.
For ultimate low maintenance, powder-coated metal and synthetic materials like polywood or recycled plastic are winners. A simple rinse with a garden hose or a wipe with a damp cloth and mild soap is usually all it takes. Stubborn dirt comes off easily without fear of damaging the finish.
Teak and other quality hardwoods are naturally resistant to rot and insects. To clean, just use a soft brush with a specialized teak cleaner or a mild soap solution. While they will weather to a silvery-gray patina naturally, this requires no cleaning effort at all if you like the look.
For painted or stained wood benches, a bit more care is needed. Use a gentle cleaner and avoid power washers, which can strip the finish. Regular dusting and prompt cleaning of spills are key.
The best practice for any bench is regular light cleaning rather than intensive scrubbing. Most daily grime washes right off. So, you can relax and enjoy your bench—spending more time sitting than scrubbing is exactly what it's designed for