Yes—sometimes. Moving an urban planter box by yourself is possible if it is small, relatively light, empty or mostly dry, and fitted with sturdy casters. A single person can also manage a heavier planter on a smooth, level path with the right tool, such as a furniture dolly or a pry bar and blocks. The key is to test the load first: gently lift one corner. If you can do that without strain and the box moves smoothly, you can probably handle it alone. If it feels unstable, too heavy, or you have to lean back or drag it, stop and ask for a second person.
Soil is the hidden weight. A large planter filled with wet soil can become far heavier than it looks, and that is when two people are usually the safer choice. You should also use two people if the planter is wide or tall enough to block your view, if you need to go up or down stairs, or if the route has slopes, soft ground, tight corners, or fragile plants that could shift. Never risk your back or let the planter tip just to save time.
To move it alone, first clear the route and wear gloves and closed-toe shoes. Remove plants, heavy inserts, or some soil if possible to lighten the load. Check that casters are unlocked and roll freely. For short moves, push from the base rather than pulling from the top, keep your back straight, bend your knees, and move slowly. For heavier boxes, use a dolly and straps, or lift one edge slightly with a lever and slide blocks underneath. Move in short stages and recheck stability as you go.
In short, you can move an urban planter box by yourself when it is small, manageable, and on an easy route. You need two people when it is large, wet, awkward, or requires stairs or lifting. If there is any doubt, use a helper—it is faster, safer, and much better for your back.