Yes, you can grow a small potentilla in an outdoor plant box! Potentilla, also known as cinquefoil, is a hardy perennial shrub that thrives in containers when given the right conditions. These compact, low-maintenance plants produce cheerful yellow, white, or pink flowers throughout the summer, making them an excellent choice for patio or balcony gardens.

To ensure success, choose a dwarf or compact variety like 'Pink Beauty' or 'Goldfinger,' which are well-suited for confined spaces. Use a well-draining potting mix and a plant box with drainage holes to prevent waterlogging. Place the container in a sunny spot, as potentillas prefer full sun but can tolerate partial shade.

Water regularly to keep the soil moist but not soggy, and feed with a balanced fertilizer in early spring. Prune lightly in late winter to maintain shape and encourage blooming. With proper care, your potentilla will flourish in its outdoor plant box, adding vibrant color to your small-space garden.