Peperomia sandwicensis
Piperaceae or Pepper family
Synonyms: Peperomia pachyphylla, Peperomia pachyphylla var. insularum, Peperomia pachyphylla var. molokaiana, Peperomia pachyphylla var. picta, Peperomia purpurascens, Peperomia sandwicensis var. robusta
ʻAlaʻala wai nui kāne
ʻAlaʻala, ʻAlaʻala wai nui, ʻAlaʻala wai nui kupa liʻi, ʻAlaʻala wai nui pehu, ʻAlaʻala wai nui pōhina, ʻAwalauakāne, Kupaliʻi (Hawai‘i Island), Kūpaoa
Singlespike peperomia
Natural Range & Environment
There are currently 25 recognized native species of Peperomia in Hawai‘i, 23 endemic species and two indigenous. Peperomia sandwicensis is one of the 23 endemic species, and is found on the islands of Kauaʻi, Oʻahu, and Moloka‘i [Flora of the Hawaiian Islands]. Joel Lau [per. comm.] has also reported that this species occurs in West Maui; however, we can not confirm this at this time.
Peperomia sandwicensis can be seen growing both on the ground and on moss-covered rocks in mesic valleys to wet forests from 250 to 1,220 m (820 to 4,003 ft) [Wagner et al. 1990].
While it's possible to find wild Peperomia sandwicensis growing on the ground, it is perhaps more frequently seen atop a moss-covered rock or log (Photograph courtesy of bellamargerin CC BY-NC 4.0.). A distinguishing characteristic of P. sandwicensis is its long single flower/fruit spike, which you can see in these two photographs, hence the common name Singlespike peperomia (Photograph of plant in white pot courtesy of Orville C. Baldos ©.). Dr. Orville C. Baldos and his team at the University of Hawai‘i at Mānoa have developed and researched the best growing conditions for two cultivars of P. sandwicensis, ‘Palikea’ and ‘Ekahanui’; cultivar ‘Palikea’ in round white pot (Photograph courtesy of Orville C. Baldos ©.); cultivar ‘Ekahanui’ in square white pot and on UHM library desk shelf (Photographs courtesy of Orville C. Baldos ©.). Another fairly reliable feature of P. sandwicensis is the red undersurface of its leaves as seen in the header photograph (courtesy of Joel Lau ©). However, the amount of red can vary from predominantly red (most common) to just a bit of red.
Description
Peperomia sandwicensis is a small (less than one foot [30 cm] tall; about one foot [30 cm] maximum diameter) succulent herb with the potential to live longer than five years in cultivation. Its fleshy stems are red to dark purple and typically hairy.
Peperomia sandwicensis has two to six succulent leaves per node that are green and hairless on their upper surface and most often all or mostly red and hairy on their lower surface. However, there are plants with only a little red on their leaves' lower surfaces. (Leaf color seems to be fixed for a single plant but varies between plants within and between populations.) Some plants have conspicuous light-colored veins on their upper surface while others do not. Leaves are elliptic to ovate and vary in size from about ⅓ inch to 1½ inches long (0.9 to 4 cm) depending on environmental conditions.
Peperomia sandwicensis has long (up to ten inches [25 cm]), usually solitary, slender flower spikes covered with dozens of very tiny perfect (bisexual) flowers. Cultivated plants bloom sporadically year-round. The pollinated flowers develop into tiny ovoid, sticky, single-seeded fruits that turn brown to black when fully mature.
The two Peperomia sandwicensis cultivars, ‘Ekahanui’ and ‘Palikea’, were propagated from cuttings collected from two wild plants in the northern Wai‘anae Mountains, O‘ahu, by Joel Lau. Orville Baldos' description of the two follows.
‘Ekahanui’ has longer stems, larger leaves, and more prominent leaf venation than ‘Palikea.’ Stems are hairy and can be upright to floppy with few branches. Stem color ranges from red-purple to grayed orange. The average internode length is 2.4 cm. Leaves are 1.4 to 2.6 cm wide and 1.7 to 3.3 cm long. The upper leaf surface is hairless and dark green with light green veins; there are three to five prominent main veins while secondary veins form a netted pattern. The lower leaf surface is hairy and red-purple. Veins on the lower surface may sometimes appear light green or pinkish. Flower spikes are floppy and can grow very long (up to 25 cm) emerging from the stem tip or the side of the stem [Baldos & Matos 2024].
‘Palikea’ has elliptic, thick, fleshy leaves 0.7 to 1.7 cm wide and 0.9 to 2.4 cm long. The upper leaf surface is hairless and dark green, usually with three light green veins radiating outward from the base of the leaf. Smaller, light green secondary veins may also appear on the upper leaf surface. The leaves' undersurfaces are hairy and red–purple with light green to pinkish veins. Stems are ascending to weakly erect and there is good branching. Stem color ranges from red–purple to grayed orange. The average internode length is 1.3 cm. Flower spikes are solitary and produced terminally or sometimes laterally. The spike can be up to 13 cm long and often has a slight curvature [Baldos et al.2021].
Growth Requirements
General
Dr. Orville C. Baldos and his team at the University of Hawai‘i at Mānoa, particularly his student, Aleta K. Corpuz (check out her MS defense video), have researched the propagation and best growing conditions for Peperomia sandwicensis (and some other native Hawaiian Peperomia). Therefore, some of the information below comes from their investigation along with our own observations.
ʻAlaʻala wai nui kāne is best grown as a container plant, preferably indoors, because of the threat posed by alien snails and slugs that will eagerly consume it. If kept outdoors, a hanging basket or other types of defenses like copper barriers deserve serious consideration.
Peperomia sandwicensis will survive and grow at quite low light levels, even lower than those needed by its sister species, P. leptostachya. If indoors, place your ʻalaʻala wai nui kāne under an LED lamp or next to a window that receives bright but indirect sunlight; Corpuz found that P. sandwicensis can survive and grow under standard LED office lights for at least six months. Outdoors, place your ʻalaʻala wai nui kāne in a site with similar light levels, bright but indirect or shaded sunlight; do not expose your plant to direct sunlight.
For our ʻalaʻala wai nui kāne, we typically used a mix of peat moss and black cinder with cinder making up at least 50% of the mix. This provides excellent water drainage and discourages stem or root rot. Baldos' team used either a 1:1 mix of coconut coir and cinder or a 1:1 mix of calcined clay and fine orchid bark for their P. sandwicensis. When watering your plant, allow the media (or soil) to become surface dry between waterings and avoid any standing water in the pot's saucer. If your plant is indoors, occasionally clean your plant by misting it with distilled water or rainwater to mimic the rainwater-washing it would normally experience outside.
Peperomia sandwicensis grows at a slow to moderate pace, typically slower than P. leptostachya, with the cultivar ‘Ekahanui’ growing larger than ‘Palikea.’ Baldos encourages regular pinching off (i.e., pruning) of the stem tips of both cultivars to promote branching and/or improve appearance, particularly for ‘Ekahanui’ which seems to be more lanky than ‘Palikea.’ Additionally, to sustain or promote growth, apply a balanced controlled-release fertilizer every 6 to 12 months, or feed your ʻalaʻala wai nui kāne with an organic or inorganic foliar fertilizer at ⅓ to ½ the recommended strength every couple of months. However, avoid overfertilizing since this will result in abnormal growth. Since P. sandwicensis is a small plant, for a larger or fuller display, Baldos suggests planting two or three plants in a single pot.
Peperomia sandwicensis will occasionally develop small plantlets near the tips of its flower spikes which can be used to propagate new plants. Additionally, it's not uncommon to see seedlings pop up in nearby pots. Lastly, P. sandwicensis can be propagated from either cut stems (easy) or individual leaves (a bit harder).
Pests and Diseases
If kept as a houseplant, you'll likely have few pest problems with your ‘ala‘ala wai nui kāne. However, outside, keep a wary eye for snail or slug damage. Keeping the plant in a container off the ground — or, better yet, in a hanging basket — will make it harder to find by these herbivores. If you decide to plant your ‘ala‘ala wai nui kāne in the ground or on a rock and the snails or slugs go after it, install barriers (copper or otherwise) around the plant, use traps, or resort to snail and slug bait poisons (see our Pests & Diseases page for a fuller discussion about what to do about snails and slugs).
ʻAlaʻala wai nui kāne are infrequently attacked by mealybugs (particularly root mealybugs), scale insects, and thrips. Refer to the Pests & Diseases page for treatments to control these pests.
Bacterial or fungal rot can be a problem if you overwater — so don't. Additionally, make sure the media in the pot or the soil at the site where your ‘ala‘ala wai nui kāne is planted drains extremely well. If you start to lose a plant because of rot, quickly take one or two cuttings from a still healthy stem and attempt to root them in new clean media (i.e., perlite, cinders, vermiculite) in order to have a replacement plant.
Uses
Ancient Hawaiian
The various Hawaiian names for our native Hawaiian Peperomia do not have a one-to-one correspondence with their more numerous scientific names. Therefore, it is currently impossible to tell if: (1) Hawaiians used all or only some Peperomia species, and (2) whether all the species were used in the same way or if different species had different uses. Additionally, the name ‘ala‘ala wai nui is shared with a completely unrelated indigenous native mint (Coleus australis; syn: Plectranthus parviflorus), which further complicates any investigation of ancient uses. With these caveats, below is what we can extract and summarize from the literature.
A grayish-green dye, called ʻahiahia or puahia, was made from the ashes of ʻalaʻala wai nui kāne leaves and stems and used to dye kapa [Krauss 1993].
A number of authors (Handy et al. [1934]; Ka‘aiakamanu & Akina [1922]; Krauss [2001]) describe medicinal uses of ʻalaʻala wai nui, most often using the name ʻalaʻala wai nui pehu, but with only a genus (Peperomia spp.) identification; it's concerning that Ka‘aiakamanu's & Akina's [1922] describes the plant as being quite a bit larger and woodier than any native Peperomia we have ever seen. The authors describe the herb being used to treat multiple ailments, including: uterine abnormalities, as a laxative for newborns, general debility, wasting away or general weakness, pulmonary diseases, chest pain, thrush, vaginal discharge, tuberculosis, and asthma. We question whether any of these treatments were efficacious because they included ʻalaʻala wai nui, given that all the prescriptions included additional plant parts from two or more non-Peperomia species. You can find the complete prescriptions in the sources listed above.
Modern
Special Features and Information
General
Piperaceae is a large family with about 3,600 species in five genera. Members may be small trees, shrubs, or herbs, with the family having a pantropical distribution. Best known are species like Piper nigrum that are used as spices [WikipediA;Piperaceae].
There are currently 25 recognized native species of ‘ala‘ala wai nui kāne in Hawai‘i, 23 endemic species and two indigenous. There is also one introduced Peperomia species, P. pellucida, which has become naturalized on Kaua‘i and O‘ahu [Flora of the Hawaiian Islands].
The sticky poppy-like seeds of ‘ala‘ala wai nui kāne have a slightly to sharply peppery taste similar to their famous cousin, black pepper (Piper nigrum). Peperomias, despite their name, are not related to bell and chili peppers, which belong to an entirely different plant family, Solanaceae or Nightshades. However, well-known local relatives of ‘ala‘ala wai nui kāne include: ʻawa or kava (Piper methystichium) and betle nut (Piper betle) — not to be confused with betel nut — which is chewed with the nut of the areca palm (Areca catechu) [WikipediA; Betel]. Both ʻawa and betle nut are stimulants.
Hawaiian Name
The various Hawaiian names for our native Hawaiian Peperomia do not have a one-to-one correspondence in the literature with their more numerous scientific names. Therefore, it is currently impossible to tell if Hawaiians had a specific name for every Peperomia species in Hawai‘i, if one or more species had a collective name or multiple names, or if some species had no Hawaiian name. Below is what we can determine from the known literature and oral Hawaiian sources.
Wai nui translates to "big water," while ‘ala‘ala translates to “ink sac in octopus or squid,” “scar of a scrofulous sore,” or “aerial tubers of bitter yam” [Pukui & Elbert 1986].
An alternative interpretation of the meaning of the plant name ‘ala‘ala wai nui was shared with me (Koebele) many years ago by a Hawaiian coworker. If we assume that ‘ala‘ala is a modification or variation of the Hawaiian word ala, which means "path" [Pukui & Elbert 1986], then the translation becomes "the path of big water." What might this big water be? How about the rain? And, where does ‘ala‘ala wai nui grow best? Well, it grows best on the side of a rock, a tree, or a cliff that faces the path of the rain.
Kāne is the Hawaiian word for man or male [Pukui & Elbert 1986]. Attaching kāne to the end of ʻalaʻala wai nui is most likely a reference to the phallic appearance of the plant's flower/fruit spike. The indigenous native mint (Coleus australis; syn: Plectranthus parviflorus), totally unrelated to native Peperomia species but frequently growing in similar habitats (e.g., on bare rocks), also has the Hawaiian name ʻalaʻala wai nui. However, it too, sometimes, has a qualifying term, wahine, the Hawaiian word for "woman" [Pukui & Elbert 1986], possibly referring to the vaginal shape of its flower.
Li‘i means "small" or "tiny." Similarly, one meaning of kupali‘i (a name used on Hawai‘i Island) is "small" or "dwarfish" [Pukui & Elbert 1986]. Therefore, this adjective and name may be referring to the small stature of these plants. One meaning of kūpaoa is "strong permeating fragrance" [Pukui & Elbert 1986], which is possibly a reference to the peppery scent of the seeds of our native Peperomia. Pehu means "swollen" or "distended" [Pukui & Elbert 1986]; it's unclear how this adjective relates to these plants. One meaning of pōhina is "to fall prone" or "topple" [Pukui & Elbert 1986], which may refer to the growth behavior of some native Peperomia.
Etymology
Peperomia comes from the Greek words peperi, meaning "pepper," and homoios, meaning "resembling," referring to its similarity to pepper plants in the genus Piper [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