Nutational aeronasty is a fascinating phenomenon in plants where they exhibit rhythmic, spontaneous movements independent of external stimuli. If you're looking to showcase this captivating behavior in your outdoor plant boxes, certain species stand out for their pronounced nutational aeronasty.

1. Mimosa pudica (Sensitive Plant): Known for its rapid leaf-folding response, this plant also displays subtle nutational movements in its stems, making it a great choice for observation.

2. Phaseolus vulgaris (Common Bean): Bean plants exhibit clear nutational growth patterns as their tendrils search for support, creating a dynamic display in plant boxes.

3. Helianthus annuus (Sunflower): While famous for heliotropism, young sunflowers also show nutational movements as their stems grow and adjust.

4. Passiflora incarnata (Passionflower): This vine’s tendrils perform elegant nutational sweeps, ideal for outdoor plant boxes with trellises.

5. Bryonia dioica (White Bryony): A vigorous climber, its stems twist and turn in nutational patterns, adding visual interest.

For optimal results, ensure your plant boxes receive ample sunlight and support structures for climbing species. Regular watering and well-draining soil will encourage healthy growth and more pronounced movements. Observing these plants can provide endless fascination and a deeper appreciation for plant behavior.

By selecting these species, you’ll create a living demonstration of nutational aeronasty right in your outdoor space. Happy gardening!