When selecting planter boxes for urban spaces like balconies, rooftops, or small patios, one feature stands above all others: excellent drainage. Without proper drainage holes at the bottom, water accumulates, leading to root rot, fungal diseases, and ultimately, dead plants. In the confined environment of a city, plant health is paramount, and it all starts with the roots' ability to breathe.
While aesthetics and size are important, a planter that traps water will undermine all your gardening efforts. Look for boxes with multiple, unobstructed drainage holes. Pair them with a saucer to protect your surfaces, but ensure the pot itself isn't sitting in standing water.
Beyond drainage, other vital features include durable, weather-resistant materials (like fiberglass, metal, or treated wood), a design that maximizes your limited space (consider vertical or railing planters), and, for convenience, self-watering systems or sufficient soil volume to maintain moisture. However, never compromise on drainage—it is the non-negotiable foundation for thriving urban greenery.