Yes, you can grow a small pomegranate tree in an outdoor plant box! Pomegranates, especially dwarf varieties like 'Nana' or 'Provence,' adapt well to container gardening. Choose a sturdy, well-draining plant box (at least 18-24 inches deep) and place it in a sunny spot with 6-8 hours of direct sunlight daily. Use loamy, slightly acidic soil and water deeply but infrequently to mimic Mediterranean growing conditions. Prune lightly to maintain shape and encourage fruiting. With proper care, your potted pomegranate can yield delicious fruit while adding ornamental appeal to patios or balconies. Protect young trees from frost and fertilize monthly during the growing season for best results.