Yes, you can grow bamboo in an outdoor plant box, but it requires careful planning and maintenance. Bamboo thrives in containers when given the right conditions, such as well-draining soil, adequate sunlight, and regular watering. Choose a sturdy, spacious plant box to accommodate the bamboo's rapid growth and spreading roots. Clumping bamboo varieties are ideal for containers as they are less invasive than running types. Ensure proper drainage to prevent root rot, and fertilize periodically to support healthy growth. With the right care, bamboo can be a stunning and low-maintenance addition to your outdoor space.