Gardening in compacted soil can be challenging, but choosing the right plants can make all the difference. If you're dealing with an outdoor plant box filled with dense, hard soil, opt for resilient species that thrive in tough conditions.

1. Yarrow (Achillea millefolium) – This hardy perennial tolerates compacted soil and adds vibrant color to your garden. Its deep roots help break up dense earth over time.

2. Daylilies (Hemerocallis) – Known for their adaptability, daylilies flourish in poor soil and require minimal maintenance.

3. Russian Sage (Perovskia atriplicifolia) – Drought-resistant and sturdy, this plant thrives in compacted soil while attracting pollinators.

4. Sedum (Stonecrop) – A low-maintenance succulent that handles hard soil with ease, perfect for sunny spots.

5. Switchgrass (Panicum virgatum) – Ornamental grass with deep roots that improve soil structure while adding texture to your plant box.

For best results, amend the soil with organic matter before planting and water deeply to encourage root growth. With these resilient choices, your outdoor plant box will flourish despite challenging soil conditions.