Scaevola gaudichaudii
Goodeniaceae or Goodenia or Fanflower family
Synonyms: Scaevola gaudichaudii var. pilosa, Scaevola menziesiana, Scaevola menziesiana var. glabra, Scaevola montana, Scaevola swezeyana, Temminckia gaudichaudii, Temminckia menziesiana
Naupaka kuahiwi
Naupaka
Ridgetop naupaka
Natural Range & Environment
Scaevola gaudichaudii is endemic to all the main Hawaiian Islands except Ni‘ihau and Kaho‘olawe. It grows on dry ridges as well as flats, in open shrublands to closed forests, from 75 to 800 m (246 to 2,625 feet) [Wagner et al. 1990], which sets it apart from other napaka kuahiwi which tend to grow in much wetter habitat.
On Oʻahu, S. gaudichaudii has been recorded only on the northwestern end of the Waiʻanae Mountains, and from widely scattered locations in the Koʻolau Mountains. It is still locally common in the Kuaokalā area of the Waiʻanae Mountains, but rare in the Koʻolau Mountains, with only about 15 known plants on Kūlepeamoa Ridge at the southeastern end of the range [Joel Lau per. comm.].
All the naupaka kuahiwi species have black fruits (when ripe) and "half" flowers. (Note this typical 5-petal flower to the rarer 4-petal flower in header photograph.) A flower-color variant from Kaua‘i (Photograph courtesy of Kenneth R. Wood [NTBG] CC BY-NC 4.0.). Two examples of mature cultivated plants.
Description
Scaevola gaudichaudii is a small to medium-sized shrub with a lifespan greater than five years. Its smooth light-green leaves are between one and two inches (2.5 to 5 cm) long and have slightly-toothed margins. It has dark yellow, brownish-yellow, orange, or rarely pinkish (only seen in photographs by us) flowers with the classic half-flower form of plants in the genus Scaevola. These perfect (bisexual) flowers can be weak to mildly fragrant. Wild Scaevola gaudichaudii appear to bloom sporadically, while cultivated plants are almost always producing flowers. The pollinated flowers develop into small purple to black drupes containing 1 to 2 seeds.
Growth Requirements
General
Second only to naupaka kahakai (Scaevola taccada), Scaevola gaudichaudii is the easiest naupaka to grow and maintain. Therefore, it's sad this naupaka kuahiwi is not more common in commercial and residential landscapes. Planted 3 to 4 feet apart, naupaka kuahiwi makes a nice informal hedge, or you can plant it alone as an accent in your garden. It also does well as a container plant. Rick Barboza, co-owner of Hui Kū Maoli Ola, recommends planting naupaka kuahiwi on the mauka (toward the mountains) side of your home and naupaka kahakai on the makai (toward the ocean) side as a reminder of the plants' origins.
Scaevola gaudichaudii does best in a site with full sunlight for all or most of the day, but can tolerate some shading. It prefers dry conditions with surface-dry soil but is tolerant of wetter sites (up to a point), provided the soil drains well. This naupaka kuahiwi can tolerate heat, drought, and strong winds. It can also endure some salt spray. It does not seem to be too picky about soil type and will grow in lava/cinder, clay, and organic-dominant soils; some wild plants have been found growing on eroded ridges.
Scaevola gaudichaudii seems to require less (to no) fertilizer compared to other naupauka kuahiwi species. However, it will benefit from yearly applications of compost or small applications of a balanced controlled-release fertilizer with minor elements. Alternatively, you can use an organic or inorganic water-soluble foliar fertilizer diluted to ⅓ to ½ the recommended strength every few months. Naupaka kuahiwi can be moderately pruned by hand.
Pests and Diseases
Naupaka kuahiwi is resistant to most pests and diseases. However, it is prone to spittlebug infestations. Additionally, ants will sometimes import, farm, and protect sap-sucking insects such as mealybugs or scale insects. Lastly, on rare occasions, we have seen naupaka kuahiwi with a mite or thrips infestation. Refer to the Pests & Diseases page for ways to deal with each of these pests.
Uses
Ancient Hawaiian
Naupaka kuahiwi fruits were used to produce a purplish-black dye [Krauss 1993].
Modern
The fragrant flowers of various naupaka kuahiwi are used in lei as seen in the book Na Lei Makamae by Marie McDonald and Paul Weissich [2003]. Therefore, it is possible the flowers were used similarly in ancient times.
Special Features and Information
General
Goodeniaceae is a family primarily found in Australia in arid and semi-arid sites, except for the genus Scaevola, which is pantropical. It contains about 400 species within 12 genera [WikipediA;Goodeniaceae].
Scaevola is the only genus in the Fanflower family (Goodeniaceae) native to the Hawaiian Islands. There are nine extant and one likely extinct species of naupaka (Scaevola spp.) native to Hawai‘i, with all but one (Scaevola taccada) being endemic [Flora of the Hawaiian Islands]. Scaevola taccada is also the only Hawaiian naupaka without a black fruit.
Hawaiian Origin Stories for the Naupaka Flower
(from In Gardens of Hawai‘i by Marie C. Neal [1965])
The story of the naupaka flower, though of recent origin, is one of the best known of Hawaii. It has several variants. Two lovers quarreled and the maiden tore a naupaka flower in two and declared she would not love her old sweetheart again until he should bring to her a perfect flower. He searched in vain all over the islands, for these flowers, whether they grew on the seashore, on the plains, or in the mountains, had become but half flowers. And it is said that he died of a broken heart.
Another story tells of a beautiful stranger who fell in love with a village youth. When he turned from her and went back to his sweetheart, the beautiful woman followed him and tore him from her embrace. Anger blazed about the woman, and they knew that she was Pele, goddess of volcanoes. She pursued the youth into the mountains, hurling lava after him. Then the gods took pity on him and transformed him into a half flower, the naupaka. Pele shrieked with rage and fled on a river of lava to the ocean. She overtook the maid, whom the gods turned into a beach naupaka. The lovers are forever separated, for the half flowers of the youth still bloom alone in the mountains, and the half flowers of the maiden blossom alone on the beach.
Supposedly, to add a happy ending to the sad story above, you must hike up into the mountains, pick a flower from a naupaka kuahiwi, and quickly hike back down to the ocean. There, you should pick a flower from a naupaka kahakai and press the two flowers together, thus rejoining the village youth and his sweetheart.
Hawaiian Name
Six upland species of Scaevola share the Hawaiian name naupaka kuahiwi, which translates to "naupaka of the mountains" [Pukui & Elbert 1986].
Etymology
Scaevola is derived from the Greek word, scaevus, meaning "left-handed" or "awkward," likely a reference to its unusual half-flower appearance [Wagner et al. 1990]. The species name, gaudichaudii, is in honor of the French botanist Charles Gaudichaud-Beaupré (1789-1854), who made some of the first descriptions and collections of Hawaiian flora [St. John & Titcomb 1983].
BPK