Yes, urban outdoor furniture can absolutely double as seating and a planter, and in dense cities that dual purpose is often the whole point. A well-designed planter bench, for example, gives people a place to sit while holding soil and plants in the same footprint. Tree surrounds with broad timber or concrete edges work the same way, and modular planter seating can be arranged into courtyards, bus stops, or pocket parks without eating up extra space.
The trick is that it has to be designed as one system, not a bench with a pot stuck beside it. The planter needs proper drainage, breathable soil, and enough root volume for the plants to survive. The seat needs a comfortable depth and height, smooth edges, and shade in hot weather. Materials matter too: powder-coated steel, aluminum, concrete, and durable hardwood can handle weather and public use, but they must be detailed so water doesn't stain the seating or rust the frame.
Maintenance is the reality check. Someone has to water, prune, and replace plants, and the soil weight has to be calculated into the structure and site. Accessibility also matters—leave clear routes, avoid sharp corners, and make sure seating is at a usable height.
When it's done well, multifunctional public furniture does more than save space. It adds greenery, supports public space design, cools paved areas, and gives people a reason to linger. So yes, seating and planting can happily share the same piece of urban outdoor furniture—as long as drainage, durability, comfort, and care are designed in from the start.