Scaevola coriacea growing in cultivation with other natives, such as Oʻahu māmane and pua kala and in another photoʻilima kū kahakai and pāʻūohiʻiaka. The classic Scaevola flower and dark fruit.

Growth Requirements

General

    Scaevola coriacea is actually easy to grow if you can keep your hands off the hose. In other words, it does not appreciate a lot of water and will begin to decline over time, especially if the soil does not have good drainage. For optimal growth and flower production, give Dwarf naupaka the sunniest, hottest, windiest, driest place you can give it. Besides being heat, wind and drought tolerant, it is also a salt-tolerant plant or a halophyte. Once Dwarf naupaka is established in the ground, there is very little reason to water it, with the exception of prolonged periods of no rainfall.

    Dwarf naupaka can be grown in a container or in the ground as groundcover, provided there is very good drainage. Use a generous amount of black cinder or crushed coral in the media mix. A "mulch" of black cinder will look presentable and is a beautiful contrast to the leaves and flowers. If you are planning to collect the occasional fruit it produces, watch for birds, especially bulbuls and doves with their keen eyesight, that will eat the dark purple fruits. I (Eickhoff) have waited in anticipation for fruit to ripen, only to see both of these birds at separate times poking around and then discovering the missing fruit was missing.

    Dwarf naupaka does fine with some hand pruning and can thicken the foliage on this prostrate shrub. But, in my opinion, though a slow grower, it looks nicest if allowed room to sprawl and prune only if necessary.

Pests and Diseases

    Scaevola coriacea does not appear to have any notable pests other than spider mites and, as mentioned previously, birds. Refer to the Pests & Diseases page for ways to deal with each of these pests.  

Special Features and Information

General

    Nine of the ten species of Scaevola spp. are endemic to the Hawaiian Islands and belong to the Goodenia family, or Goodeniaceae. The rare and endangered Scaevola coriacea is one of two species found along the shorelines, along with Scaevola taccada var. taccada. They are easily distinguished apart. First of all, S. coriacea is much, much rarer than the ubiquitous S. taccada. Second, S. coriacea is prostrate or nearly flat to the ground with small leaves (1-2 inches); S. taccada has larger leaves (3-9 inches) and is upright and bushy, though there are some prostrate forms. Third, the fruit of S. coriacea is about the size of a pea and dark purple; S. taccada is about the size of a small to medium olive, white or whitish yellow and pithy or spongy. 

    USFWS 2010 notes that "the pollinators of Hawaiian species of Scaevola included native bees (Hylaeus spp.), non-native honey bees (Apis mellifera), a few birds, and ants.  Because the genus Scaevola is protandrous (male flower parts appearing before female parts), in order for pollination to occur, visitors must not only contact the indusium (a specialized cup shaped structure at the tip of the female reproductive part), but they must also visit both male and female phases of the flowers. In Scaevola coriacea, the indusium was contacted only at the male phase of flowers, so no pollination was possible. Since native bees were not observed visiting Scaevola coriacea, as they must have in the past, pollination is apparently a factor that must be considered in the conservation of this species."

Hawaiian Name

    There is no known ancient Hawaiian name. Some have chosen to use a modern Hawaiian name, Naupaka papa. At this time, this website has chosen to use a popular name Dwarf naupaka, until an ancient Hawaiian name has been located.

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 specific epithet, Scaevola coriacea is from the Latin coriaceus, tough or leathery, corium (the leaves) [Gledhill 2008].