A perennial indigenous plant that forms a prostrate herbaceous vine ground cover. The flowers are 1-inch yellow, pea-shaped, slightly waxy, and arranged in clusters of 1-6. When pollinated, nanea will produce ¼-inch long reddish-brown dehiscent (will split or burst open when ripe) seedpods, which helps with local seed dispersal. Nanea have green oval to oblong shaped leaves that are sparsely to moderately covered with coarse hair. Leaves are trifoliate, arranged alternately, and have a smooth leaf margin.
Habitat & Uses
Nanea can be found naturally occurring in dry coastal areas across the main Hawaiian Islands (except Lanaʻi and Kahoʻolawe) from sea-level up to 1000 feet in elevation. Typically, they grow along sandy beaches and more rarely found inland and along sea cliffs. You can commonly find nanea growing between naupaka kahakai, ʻakiʻaki, and pōhuehue. This species is pantropical and can be found from East Africa, to areas of the Atlantic and Caribbean, and throughout the Pacific. In traditional Hawaiian medicine, the leaves, stalk, kua (midrib), and stems were pounded until soft and applied to wounds and hēhē (boils, running sore, ulcers). Additionally, the flower and seeds seem strong enough for use in lei-making. In other parts of the Pacific, Vigna marina is used in food, livestock feed, cover cropping, and traditional medicine to treat stomach ache, asthma, and skin sores.
Nanea is a nitrogen-fixer in the Fabaceae family and provides a readily available nitrogen source for any plants growing nearby. This makes nanea an excellent groundcover or accent plant as long as you provide ample room for the plant to spread (up to 6 ft.). Additionally, this vine works well in open, sunny areas and coastal climates, making it perfect for erosion control along beach or coastal cliff properties. Nanea, being a vine, can also function as trellis or fence climbers for added privacy. On a larger scale, this species would be a great choice for dune stabilization, pollinator habitat, and coastal restoration. However, it should be noted that this plant has the potential to climb up and smother other desired plants, therefore any unwanted growth should be monitored and trimmed.
In Hawaiʻi, nanea is cultivated for landscaping purposes in nurseries. It can be grown outside of its normal range and in soil not typical of coastal environments. Propagation is commonly from seed and can be facilitated with light scarification or a 24-hour soak. Propagation can also be done by cutting at a woodier portion of the plant and transplanting into well-drained soil. Use of a rooting hormone may improve results. Nanea is prone to pest issues from ants, spider mites, leaf miners, and seed weevils. They should be treated with a pesticide specifically for mites. Nanea is a great low-maintenance addition to any nursery as it’s fast growing, wind/salt/drought tolerant, and flowers throughout the year.
This plant comes with many common names and depends on the island or region you are within. The most widespread Hawaiian common names are nanea, mohihihi, or lemuomakili. The word nanea in the Hawaiian language evokes the feeling of having a good time and can be interpreted as interesting, tranquil, enjoyable, leisure, relaxing, at-ease, engaging, and amusing. This could be referencing how nanea behaves along the beach, while the next name spotlights its habit. Mohihihi can be broken up into mo-, which is short for moku meaning to be cut, severed, divided and -hihi meaning to entangle, creep, intertwine. Lemuomakili can be translated to cracked buttocks, which likely refers to the flower shape. In terms of its scientific name, the genus Vigna honors Dr. Dominico Vigna, a professor of botany at the University of Pisa. Marina refers to the species’ salt tolerance.
- Cultural significance
- Erosion control
- Nitrogen fixer
- Privacy / screening
- No dangers