Family: Oxalidaceae

ʻIhi ʻai (Oxalis corniculata) is a small indigenous herb that likes to grow in disturbed areas. The leaves look like 3-leaf clovers and grow along a creeping prostrate stem with small hairs. Bright yellow 5-petaled flowers form in small clusters. The fruit are cylindrical capsules that look like corn on the cobs and when ripe, they will explosively dehisce when touched. The tiny sesame sized seeds can also survive going through the gut, which is important as humans, birds, and other animals love the fruit’s sharp tangy flavor (like skittles!). Although edible, consumers should be aware that this plant harbors oxalic acid. High amounts of oxalic acid can lead to kidney stones, gut irritation, and other severe health conditions.

Habitat & Uses

ʻIhi ʻai can be found growing in poor soils, disturbed areas, abandoned agricultural fields, and along roads. This sun-loving herb prefers well-drained soils with lots of sand and rocks. O. corniculata is highly tolerant to disturbance, allowing it to thrive even in gravel, compact soil, and sidewalk cracks. This plant is resilient because it can regrow from stolons, tolerate wide environmental conditions, and rapidly reproduce. These qualities are also the reason why some consider this plant a weed in lawns, gardens, and nurseries.

There were not many recorded uses for this plant in Hawaiʻi, which may be because it arrived unintentionally with  early Polynesian settlers. Another equally plausible theory is that their tiny ballistic seeds either traveled stuck to a bird or inside their belly. Regardless, ʻihi ʻai is known to be present in Hawaiʻi largely before Western contact and   archaeological surveys found O. corniculata in sediment from 15th and 17th centuries. Modern use of ʻihi ʻai involves using the fruit as a salad topping.  In Hawaiian culture, ʻihi ʻai is primarily used as a laxative, but in other parts of the world the whole plant can be utilized to treat fever, nausea, and skin issues. Boiling the whole plant will give you a yellow dye, while just the flowers results in a range of colors from yellow to red and brown.

Landscaping & Cultivation

This plant requires no maintenance once established. ʻIhi ʻai will grow in a wide variety of environments, but it does prefer full sun, well-draining soil, and loamy acidic conditions. Once mature, this plant can quickly spread with seeds blasting over 10 ft. from the originating fruits. So, just be prepared for weeding if you do not want this plant to spread too far. ʻIhi ʻai happily grows from seed and cuttings.

Name Origins

In ʻŌlelo Hawaiʻi, ʻihi is the word for all wood sorrels, which can have yellow, white, red, or pink pua. ʻIhi can also refer to our four native portulaca species. There is also a connection to ʻihiʻihilauākea also known as ʻihiʻihi or ʻihi lāʻau (distinguishing it from the edible ʻihi ʻai). Although ʻihiʻihi shares similar clover-like foliage to O. corniculata, it is actually a tiny fern that only appears magically in dry lowland ephemeral ponds on Oʻahu and Molokaʻi. The name ʻihiʻihilauākea is shared with the crater near Hanauma Bay where this fern is found, the name of the local wind, and the name of a beautiful aliʻi wahine from Waimānalo who excelled at fishing and surfing.

All of the different ʻihi share one common physical characteristic, which is their alternate paddle shaped leaves. All of these ʻihi also grow in the harshest environments – along roadways, bare lava, coastal dunes, volcanic tuff, sea cliffs, steam vents, cinder cones, and rare-occurring ephemeral ponds. It is no wonder that ʻihi in ʻŌlelo Hawaiʻi means sacred, holy, majestic, or dignified. All of these ʻihi can thrive in adversity, just like a great aliʻi.

Plant Uses:

• Container plant
• Cultural significance
• Edible
• Medicinal

Plant Dangers:

• Toxic to animals and humans