Jacquemontia sandwicensis
Convolvulaceae or Morning glory family
Synonyms: Convolvulus sandwicensis, Ipomoea ovalifolia var. pubescens, Ipomoea ovalifolia var. tomentosa, Jacquemontia ovalifolia subsp. sandwicensis, Jacquemontia sandwicensis f. hosakai, Jacquemontia sandwicensis var. laevis, Jacquemontia sandwicensis var. tomentosa
Pāʻū-o-Hiʻiaka
Kākuaohiʻiaka, Kaupoʻo, Pāʻūohiʻiaka
Oval-leaf clustervine
Natural Range & Environment
Jacquemontia sandwicensis is endemic to all the main Hawaiian Islands. It grows in coastal areas on a variety of substrates, including basalt, coral, sand, and clay, and is generally more common on the leeward sides of the Islands [Flora of the Hawaiian Islands].
Pāʻū-o-Hiʻiaka was previously considered only a subspecies (i.e., Jacquemontia ovalifolia subsp. sandwicensis) of the more widespread species Jacquemontia ovalifolia; some taxonomists still consider this older standing more valid. Jacquemontia ovalifolia has the widest range of any species in the genus Jacquemontia, and is classified in different regions as separate subspecies. J. ovalifolia subspecies ovalifolia is found in Africa, while J. ovalifolia subspecies obcordata grows in Mexico and the West Indies, and, of course, J. ovalifolia subspecies sandwicensis is endemic to Hawai‘i. The species is believed to have originated in America, but the method of dispersal is currently unknown [NTBG].
Jacquemontia sandwicensis can vary in both leaf and flower characteristics. Here are two examples: a wild pāʻū-o-Hiʻiaka with glabrous leaves and white flower, and a wild pāʻū-o-Hiʻiaka with pubescent leaves and light purple flower. A rocky Maui coastline covered with pāʻū-o-Hiʻiaka (Pubescent plant and coastline photographs courtesy of Forest & Kim Starr CC BY 2.0). Two pāʻū-o-Hiʻiaka cultivars: ‘Leeward Community College White’ and ‘Puhala Bay’ (Cultivar photographs (cropped) courtesy of O.C. Baldos & D.K.S. Antesco CC BY-NC-ND 4.0 and O. C. Baldos, T. Sherrill, and D.K.S. Antesco CC BY-NC-ND 4.0).
Description
Jacquemontia sandwicensis is a herbaceous non-climbing vine, with a lifespan greater than five years, that often roots at its nodes. Like other members of the Morning glory family (Convolvulaceae), pā‘ū-o-Hi‘iaka has partially-folded leaves along the mid-vein and tubular flowers. The elliptical leaves can be densely tomentose (fuzzy) to glabrate (hairless), and are 1 to 2 inches (2.5 to 5 cm) long. Perfect (bisexual) flowers are pale purple, pale blue, or white. Pā‘ū-o-Hi‘iaka blooms after significant rains in the wild and year-round in cultivation. The fruit is a dry tan capsule divided into two sections (carpels) with each section holding 1 to 4 wedge-shaped seeds.
Growth Requirements
General
Jacquemontia sandwicensis is an excellent groundcover that can be planted in sites near the ocean prone to salt spray where other plants would perish. Some varieties also do well inland in dry sites. Although best adapted to coralline, basalt, or sandy substrates, pā‘ū-o-Hi‘iaka will also grow reasonably well in denser soils, including clays. For a dense groundcover, place new plantings 1 to 2 feet apart.
Pā‘ū-o-Hi‘iaka does best in a site with full sunlight for all or most of the day, but can tolerate a bit of shade. It requires little to no watering once established, and while frequent watering may increase growth and foliage, it can also lessen flower production. Try using a dilute fertilizer if your plants seem to grow too slowly to maintain ground cover. Hand-prune only to encourage branching or keep plants confined to a selected area.
For coastal restorations, pā‘ū-o-Hi‘iaka is one of my (Koebele) go-to plants, and there are several sites on O‘ahu where plantings have survived, persisted, and reproduced for many years. In contrast, I have never had this level of success with inland plantings. Nearly always after two to three years, some pest would attack these inland plants and overwhelm my ability to keep them alive. However, other native plant enthusiasts I have talked with have kept their pā‘ū-o-Hi‘iaka alive in their inland gardens for a much longer time. I suspect there are varieties of pā‘ū-o-Hi‘iaka that do better than others at inland sites; one variety I know does particularly well at Leeward Community College in Pearl City. Other factors, such as watering, soil type, and companion plants, may also be responsible for the varied survivorship I have observed.
If you live inland and have repeatedly failed with pā‘ū-o-Hi‘iaka in your landscape (after trying a few different varieties), we recommend keeping it as a container plant. In a container, it is much easier to monitor and treat your plant if it is attacked by pests or simply move it to a safer location. A pā‘ū-o-Hi‘iaka in a hanging basket on your lanai can be a particularly beautiful display. Recently, Orville C. Baldos, along with other researchers at the University of Hawai‘i at Mānoa, have been studying and promoting different cultivars of pā‘ū-o-Hi‘iaka. Check out what he and his colleagues have been doing at the Sustainable Ornamental Horticulture Lab (https://sites.google.com/a/hawaii.edu/baldos-lab/).
Pests and Diseases
Pā‘ū-o-Hi‘iaka can be plagued by sap-sucking pests such as mealybugs, whiteflies, and scale insects. Refer to the Pests & Diseases page for ways to combat these pest insects. Often, because pā‘ū-o-Hi‘iaka grows along the ground, it is easy for ants to reinfest plants with mealybugs, etc., at multiple points, turning pest control into a game of whack-a-mole. If the job becomes overwhelming, consider moving your plants back into pots. This will make it easier for you to treat them or move them to a safer location. Herbivorous snails and slugs will also attack pā‘ū-o-Hi‘iaka. Refer to the Pests & Diseases page for ways to combat snails and slugs. Lastly, there is some anecdotal evidence suggesting that regularly misting your plant with seawater may be a prophylactic for pests as well as a natural fertilizer.
Uses
Ancient Hawaiian
Records of the uses of pā‘ū-o-Hi‘iaka are nearly all based on translations of Reverend David Kaluna M. Ka‘aiakamanu's accounts, and are not mentioned by other Hawaiian ethnobotanists. Below are two of these records:
"As a remedy, this is good for babies having general weakness of the body. It is also good for cuts. This is mixed with taro leaves and pounded with salt. When the leaves and stems are dried, they make good tea. They are also eaten with dried coconut."[Ka‘aiakamanu & Akina 1922].
"It is a medicine for ‘Ea [thrush PE 1986, 36] and Pā‘ao‘o [childhood disease with physical weakening PE 1986, 298]. It is suitable medicine for babies and grown ups. It is a medicine that is poured for ‘Eha maka‘u [frightening pains or aches] and other ulia [accidents], too. It is pounded with Kalo stalks (hāhā) and applied to the sore or wound, and it is also drunk as a tea. It has many useful benefits." [Ka‘aiakamanu 2003].
Modern
According to Ingelia White, retired Instructor of Botany, Agriculture, and Microbiology at both Windward and Leeward Community Colleges on O‘ahu, the young leaves of pā‘ū-o-Hi‘iaka are edible and very delicious in fritters. Here is her recipe (with photograph) via Greg Koob's Hawaii Horticulture blog:
Pā‘ū-o-Hi‘iaka Fritters
50 pā‘ū-o-Hi‘iaka (young) leaves
3 Tbl all-purpose flour
1 Tbl corn starch
2 cloves garlic, pressed
Pinch of salt, black pepper, sugar
Vegetable oil
Mix flour with water to make a batter. Add pressed garlic, salt, pepper, and sugar to taste. Heat oil. Use five pā‘ū-o-Hi‘iaka leaves per fritter. Dip the leaves and pile them into the batter. Pick the fritters up by hand and fry them into one fan-shaped fritter until light brown. Serve while still hot and crispy.
Special Features and Information
General
There are more than 1,650 species within about 60 genera in the Morning glory family (Convolvulaceae), distributed worldwide [WikipediA;Convolvulaceae].
Recently, pā‘ū-o-Hi‘iaka was raised to the species level as Jacquemontia sandwicensis, where formerly it was considered an endemic subspecies of Jacquemontia ovalifolia. One non-native relative, the Skyblue clustervine (Jacquemontia pentantha), is naturalized on Oʻahu. Pāʻu-o-hiʻiaka is related to the locally popular foods ʻuala or sweet potato (Ipomoea batatas) and ung-choi or swamp cabbage (Ipomoea aquatica).
In addition to Jacquemontia sandwicensis, native Hawaiian members of Convolvulaceae include: the endemic and endangered Bonamia menziesii; the indigenous makihi (Cressa truxillensis); the endemic and parasitic kauna ʻoa (Cuscuta sandwichiana); the indigenous hunakai (Ipomoea imperati), koali ʻawa (I. indica), White-flowered beach morning glory (I. littoralis), and pōhuehue (I. pes-caprae subsp. brasiliensis); and the endemic Hawaiian moon flower (I. tuboides).
Hawaiian Name
Early one morning, Pele carried her baby sister Hi‘iaka to the ocean, laid her down on the beach, and left her to go surfing. As Pele surfed, the sun began to rise high in the sky and burn the sensitive skin of Hi‘iaka. Nearby, a native vine saw what was happening to Hi‘iaka and quickly grew to cover the baby and protect her. Hours later, Pele returned from surfing but could not find her sister. Finally, she discovered Hi‘iaka hidden under the many leaves of the vine. Only then did she realize how irresponsible she had been and spoke to the vine, "Thank you, protector of my beloved sister. From this day forward, you will be known by all the Hawaiian people as Pā‘ū-o-Hi‘iaka, the skirt of Hi‘iaka" [Neal 1965].
In reference to the name kākuaohiʻiaka, the word kākua means "to bind or fasten on, as a sarong or belt" [Pukui & Elbert 1986].
Etymology
Jacquemontia honors Victor Jacquemont (1801–1832), a French botanical explorer [Wagner et al. 1990]. The species name, sandwicensis, refers to the "Sandwich Islands," as the Hawaiian Islands were once called and named by James Cook on one of his voyages in the 1770s. James Cook named the islands to honor John Montagu (The fourth Earl of Sandwich) for supporting Cook's voyages [Gledhill 2008].
BPK