Maiapilo has fragrant night-blooming flowers. The following morning, as the flowers begin to wilt, they often turn an attractive pink for a few hours (Photograph courtesy of cprice CC BY-NC 4.0.). Here, maiapilo's stinky ripe fruit is split open to reveal viable (dark) and inviable (light) seeds (Photograph courtesy of Forest & Kim Starr CC BY 2.0). A wild (Kalaeloa, O‘ahu) and cultivated maiapilo (Pearl City, O‘ahu). Header photograph courtesy of Sebastian Marquez ©. 

Growth Requirements

General

    Prostrate forms of Capparis sandwichiana can be used as a groundcover, while more upright plants are best displayed as a single accent or clustered to form a barrier or informal (i.e., lightly pruned) hedge. Maiapilo can also be kept as a container plant. 

    All forms do best in a site with full sunlight for all or most of the day and do poorly in fully shaded sites. Maiapilo can tolerate high temperatures, drought, strong winds, and salt spray. They can be grown in a variety of soils or media but do best in soils that are predominantly coralline or lava/cinder. Good drainage is essential; planting your maiapilo on a mound of crushed coral or cinder is an easy way to meet this requirement if you are in doubt. 

    Potted and newly-planted maiapilo require regular watering (i.e., one to two times a week). However, after three or four months in the ground, maiapilo requires little to no watering. In fact, overwatering is a sure way to kill an established maiapilo. 

    Once established in the ground, maiapilo often grows rapidly and begins producing flowers after one or two years. While maiapilo has a long flowering period, the plant does occasionally take a break, so, don’t expect to see those big fragrant flowers every evening. A small amount of fertilizer when transplanting, and a balanced (e.g.,13–13–13;NPK) slow-release fertilizer with micro-nutrients applied once or twice a year can improve their growth and vigor. 

    Today, alien birds often come to eat the pulpy flesh and seeds inside a ripe maiapilo fruit and unwittingly scatter the seeds (for possible regeneration) — a role extinct native fruit-eating birds may have played in the past [Foster & Robinson 2007]. Therefore, if you intend to collect seeds to sprout or store (in your refrigerator), you need to either beat the birds to the ripe fruits or protect the unripe fruits with a netted "party-favors" bag.

    In the field, we have visited maiapilo that are at least ten years old. However, to date (2025), neither of us has been able to keep a cultivated plant alive for that long. Our plants' deaths have sometimes been sudden and unexpected, suggesting a disease or pest in the soil. While other times, the plant appeared to slowly senesce and then die. These experiences suggest that we are still missing something important regarding the proper horticulture of this beautiful plant. If you have had better success than us (e.g., a ten-year-old maiapilo), we would greatly appreciate you contacting us at EickhoffandKoebele@gmail.com and sharing your insights so that we can share them with others reading this page. 

Pests and Diseases

    The most serious killer of maiapilo in the ground is overwatering, particularly for maiapilo planted in dense soils (e.g., clay). Therefore, don't make this mistake. When newly-planted, small maiapilo should be protected (e.g., wire cage) from snails, slugs, rats, and mice, which can girdle and kill them. Cabbage butterfly caterpillars and leaf-cutting bees sometimes target maiapilo leaves, making them unsightly. Powdery mildew will afflict maiapilo mistakenly planted/placed in a wet shady site. 

    After more than two decades of observation, we still cannot explain why, occasionally, one or two of a plant’s stems will quickly yellow and wither, although this phenomenon is more common during Hawai‘i’s wetter winter season. Until someone does figure this out, the safest thing to do is to quickly prune and discard the dead stem. 

Special Features and Information

General

    Capparaceae is a small family of about 430 species within 15 genera [WikipediA;Capparaceae]. Capparis sandwichiana is the only native Capparis in the Hawaiian Islands. There is debate as to whether the genus Capparis should be moved into the Mustard family (Brassicaceae), or retained in its own family, Capparaceae. 

    Maiapilo is an important species for the rare endemic Blackburn's Sphinx moth (Manduca blackburni), which feeds on the nectar of its flowers [USFWS 2022].

Hawaiian Name

    Maiapilo translates as "stinky banana," likely referring to the fruit that looks like a tiny banana, turning from green to yellow when ripe, but has a particularly bad scent. Maiapilo flowers, in contrast, have a pleasant lemony fragrance!

    The early common people of Niʻihau referred to the plant as pilo or puapili, while chiefs called it maiʻa a Maui, translated as "the banana of Maui" [Wichman & St. John 1994].

Etymology

    Capparis comes from the Arabic word kabar, for capers (Capparis spinosa), through the Greek word kapparij, and then into Latin [Gledhill 2008]. The species name, sandwichiana, is a reference to the "Sandwich Islands," the name given to the Hawaiian Islands by James Cook on one of his voyages in the 1770s. He named the islands after John Montagu (The fourth Earl of Sandwich) for supporting his voyages [Gledhill 2008].