Hydrocotyle bonariensis
largeleaf pennywort
Overview
Hydrocotyle bonariensis is a low, colony-forming perennial in the family Araliaceae, spreading by long underground rhizomes and surface stolons. Its rounded leaves are peltate, with the stalk joined at the center of the blade, 1–3 inches (2.5–8 cm) across, glossy green, with scalloped margins and radiating veins; they are held singly on upright petioles 4–14 inches (10–35 cm) tall. From summer into early autumn it produces branched flower stalks bearing several tiers of small greenish-white flowers in whorled umbels, followed by flattened ribbed fruits. The plant grows on coastal dunes, beach swales, sandy roadsides, and the moist margins of brackish wetlands along the southeastern and Gulf coasts of North America, tolerating salt spray, sand burial, and periodic flooding. Its vigorous rhizomes let it bind shifting sand, but the same habit makes it spread aggressively into lawns, beds, and paths, where it is hard to remove once established. It roots at the nodes as stolons run, so fragments left in the soil regrow readily.
Native Range
Hydrocotyle bonariensis is native to the coastal plain of the southeastern United States, from North Carolina south through Florida and west along the Gulf to Texas. It also occurs along the coasts of Central and South America. It is largely restricted to sandy, salt-influenced habitats near the shore.Suggested Uses
Hydrocotyle bonariensis is used for dune stabilization, erosion control on sandy sites, and as a salt-tolerant groundcover in coastal plantings. It is also grown as a contained foliage plant in water gardens and pond margins. Because of its spread, it is kept out of mixed beds where it can overrun neighbors.How to Identify
Appearance
Size & Dimensions
Height4" - 1'2"
Width/Spread1' - 3'
Bloom Information
Small greenish-white flowers appear from June through September in branched, tiered clusters held among the leaves. Individual umbels are inconspicuous, but flowering continues over much of the warm season, roughly 8–12 weeks. The ribbed fruits that follow split into two seeds at maturity.
Detailed Descriptions
Foliage Description
glossy greenGrowing Conditions
Sun Requirements
Requires 4-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Hydrocotyle bonariensis grows in full sun to part shade on sandy soils and tolerates a wide moisture range, from droughty dunes to seasonally wet swales. It withstands salt spray, brief flooding, and sand burial, which suits it to coastal stabilization. In garden soil it spreads quickly by rhizomes and stolons, so it is usually confined to containers or bordered beds with a root barrier. It needs no fertilizer and little water once rooted. Pieces of rhizome left in soil resprout, so thorough removal is needed when reducing a stand.Pruning
No formal pruning is needed. Running stolons are trimmed back to hold the plant within bounds, and flower stalks can be removed if self-seeding is not wanted. Mowing tolerates the low foliage but does not eliminate the rhizomes.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons