That's a fantastic question that gets to the heart of functional urban design. The goal is to make bins easy to find without making the street look harsh. Here’s a natural, practical approach.
First, think beyond just "bright." High-visibility doesn't always mean neon green or safety orange. Consider high-saturation versions of more muted tones. A deep, vibrant blue or a rich burgundy can stand out against concrete and greenery without being jarring. Many cities successfully use dark green or charcoal grey; they recede visually but are still identifiable as public fixtures.
Context is everything. Look at the surrounding area. In a historic district, a deep bronze or forest green might blend respectfully. In a modern park, a crisp sage green or slate blue could work well. The key is contrast. A mid-tone sand color will disappear on a beige sidewalk, but a deep red or navy will pop.
Consider using color strategically. You don't need the entire bin to shout. A neutral base color (like grey, black, or dark green) with a brightly colored lid or a bold, colored band for the opening can be highly effective. This draws the eye to the point of use while keeping the overall structure subtle.
Also, standardize colors by function if possible. This is a huge win for usability. For example, use blue for recycling and green for general waste consistently across the city. This uses color for clear communication, not just visibility.
Finally, test it! Paint a sample panel and view it in different lights—sunny, cloudy, night. See how it looks next to buildings, trees, and pavement. The right color is visible but feels like it belongs, making the city cleaner and more pleasant for everyone.