Yes—self-watering urban planter boxes are widely available, and they can make urban gardening much more forgiving if your schedule is busy. Most models use a water reservoir at the bottom, a wick or capillary mat that pulls moisture into the soil, a fill tube, and an overflow hole. Some also include a water-level indicator, so you can see when to top up instead of guessing.
These self-watering planters do not mean you will never water again. In mild weather, many balcony planter boxes need refilling every one to two weeks; in hot, windy, or sunny conditions, you may need to refill every few days. Rain can help if the planter is outdoors, but do not rely on it. Check the reservoir regularly and keep it from drying out completely, especially while plants are establishing roots.
For best results, use a light, well-draining potting mix rather than garden soil, and choose plants that suit the planter's size and light exposure. Make sure the overflow is working so excess water can escape, and avoid compacting the soil. Self-watering designs are excellent for low-maintenance watering on balconies, patios, rooftops, and small city spaces, but they still need occasional inspection, cleaning, and seasonal adjustments. If you want the closest thing to set-and-forget watering, look for a quality self-watering planter box with a large reservoir, a clear water indicator, and reliable overflow drainage.