Beach jacquemontia is a perennial vine with stems only about 3 feet long. Its stems usually sprawl on the ground. The leaves are fleshy, elliptic to rounded egg-shaped, 0.4 to 1 inch long, and generally upright with the flat surface vertical. Younger leaves and stems have enough soft down to appear whitish.
Flowers are in the axils of the leaves, in groups or solitary.
The outer sepals of the flowers have tiny hairs along their margins, a characteristic that distinguishes the species from Jacquemontia curtissii . The fruits are capsules. Jacquemontia curtissii , which inhibits pinelands on the southeast Florida mainland, has hairless sepals and narrower leaves that are not fleshy. The species historically occurred at Jupiter Island in Palm Beach and Martin Counties. All but one of the sites are parks or recreation areas by State, County, or local governments.