Absolutely! Pairing plants in an urban planter box is an art that combines aesthetics and plant science. The key is selecting plants with similar needs for sunlight, water, and soil. A classic design principle is "Thriller, Filler, Spiller": use one tall, striking plant (Thriller like dwarf ornamental grass), several mid-height bushy plants (Filler like coleus or petunias), and trailing plants that spill over the edge (Spiller like ivy or sweet potato vine).
Consider companion planting for health and yield. For an edible box, pair basil with tomatoes to enhance flavor and repel pests. Marigolds are excellent fillers that deter aphids. Always ensure proper drainage and a large enough container for root growth. With thoughtful pairing, your planter will become a lush, productive urban oasis.