This garden is part of Waimea Valley's effort to provide protective cultivation for our rarest native plants, studying propagation techniques and keeping accurate records, all in hope of restoring self-sustaining plant communities for future generations to enjoy.
The Hawaiian Islands are volcanic in origin and more than 2000 miles from the nearest land mass. Plants evolved without the need of stinging hairs or spines for protection, because predators, such as grazing animals, did not exist in these early times. Insects and birds (many of them flightless) dominated. Our only native mammals, the hoary bat and monk seal, had little impact on plant life. The rich flora of Hawai`i is descended from a small number of pioneering ancestors, all of which arrived by wind, wave or wing. Most evolved into new species so that today over 90% of our Hawaiian plants are found nowhere else, the highest rate of endemism in the world.
Many plant species evolved in isolated habitats like a small swamp or gulley. Geothermal activity, rapid erosion and fierce storms fractured plant communities forcing plants to adapt. Although the early Polynesians cleared land for cultivation, for the most part they co-existed with nature and these important habitats. It was not until the arrival of the Europeans that the delicate balance of nature was disturbed. The process of clearing land for plantations and the introduction of goats, cattle and deer all took their toll on Hawai`i’s plant life.
There 3 large gardens devoted solely to Hawaiian plants. The largest and oldest, Hawaiian A, surrounds Pond 2, and you walk past it from the ticket booth to the first bridge. About a third of the way up the Valley, above the upper road, is Hawaiian B which gets morning light, but is shaded by the steep Valley wall by mid-afternoon. The newest, Hawaiian C, is in full sun and has been planted in the Makai end of the Erythrina Collection behind the oracle towers of the Lono Heiau ( a Hawaiian temple whose rock work has been carbon-dated to the 1400’s) visible from the main parking lot.
We have recently extended the Hawaiian flora collection to the area across the road, behind the Kokua Kiosk. Before the first bridge is a tall rock pile planted with Kaua`i endemic plants. The oldest of the tall islands, Kaua`i had more time for plants to specialize and evolve into new species. On the other side of the bamboo-topped fence are plants endemic to O`ahu. In this area you can see the large bell-shaped flowers of Abutilon sandwicense, only found in the Wai`anae Mountains. Also here are plants of popolo, Solanum sandwicense, related to the tomato. Wild plants of these have become extinct on O`ahu in the time since they were brought into Waimea's protective cultivation. In a cage is a very rare, small carnation relative which naturally occurs only in Diamond Head crater. A seedling from O`ahu's last Gardenia brighamii tree is planted by the bamboo fence, and next to it is the rare kauila, Colubrina oppositifolia, with some of the hardest wood of all the native trees. At the other end of this area is a sprawling beach plant, the `ohai, Sesbania tomentosa. It has silvery leaves with microscopic hairs to withstand the heat and drying winds. This was propagated from the very last plant growing on Kaohikaipu Islet, off the coast from Makapu`u in the southeast. Behind it is the rarest of O`ahu's loulu palms, Pritchardia kaalae, collected on and named for O`ahu's tallest mountain.
The genus hibiscus adds a great variety of color to the Hawaiian flora. Surprisingly, the bright red Hibiscus kokio flowers are descended from the same pioneer ancestor that evolved to become our two white-flowered species: H. waimeae from Kaua’i named for Kaua’i’s Waimea Canyon and H. arnottianus found on O' ahu. These two native whites, Koki`o ke`oke`o, are the only hibiscus in the world that give off a faint perfume at dawn and dusk.
For no good reason, the state flower used to be a Chinese red hibiscus. That was changed in the late 80’s when the bright yellow-flowered endemic Hibiscus brackenridgei, Ma`o hau hele, was given that honor. This endangered species survives in the wild in very few places. Fires in 2007 impacted the already limited range of the O’ahu subspecies Mokuleianus. Lana’i’s last few plants are not doing well, but several collections are growing well at Waimea.
One of our native hibiscus species is indigenous. H. furcellatus, `Akiohala, with big pink flowers, got to Hawai’i without man’s help, but wild plants of this species can also be found in Mexico and the Caribbean.
The jury is still out as to whether the hau tree, H. tiliaceus, is a native or a Polynesian introduction. Unusual forms of these trees are planted along the banks of the stream above the first bridge. Taxonomists will soon put the hau tree in to a new genus, Talipariti.
The Hawaiian Hibiscus collection is large. Four sections separated by roads and paths start at the Hale ‘Iwi burial site and extend down to the main road makai of the banyan tree.
In ancient Hawai‘i, plants played an important part in all aspect of life. Plants were not only a food source, but were used in medicines, building, clothing, weapons, and as food containers.
The kāhuna were skilled in utilizing the plants around them for medicines and religious ceremonies. The ti plant was used to reduce fevers, while the ginger root was mashed and mixed with salt water for a purification mixture. kō (sugar cane) juice helped make medicines more palatable.
Early Hawaiians used koa wood for building canoes and surfboards, and the wauke for pounding into tapa cloth. Leaves of the ahuhu were crushed and put in tide pools where it made fish an easy prey by immobilizing them.
This garden highlights many of the plants utilized by ancient Hawaiians and has individual markers telling the specific uses. A row of ti plants separates the edible from the non edible plant sections. The small medicinal garden is planted under and around 2 Milo trees.
As you enter this collection from the upper road you'll see an 'ulu (breadfruit) tree, and beyond it are tall, flowering ko (sugar cane) plants surrounding three fenced kalo (taro) plantings. Hawaiian varieties of mai'a (banana) are planted near the kalo beds, and beyond them are two 'ohi'a 'ai (mountain apple) trees from the South Pacific which fruit twice a year. The ground covers under the sugar cane are varieties of 'uala (sweet potato). These can be recognized by their flowers which resemble miniature morning glories which are closely related.
Our named varieties of 'uala are being grown the traditional way a bit further up the Valley- the tubers grow in loamy soil in low rock cylinders. You can see these by the edge of the grass near the banyan tree.
After walking past the kalo beds you'll see a row of ti plants separating the edible from the non-edible plant sections. A medicinal garden is planted under and around two milo trees, hibiscus relatives with excellent wood brought by the Polynesians. Across the trail in the non-edible section are two calabash trees. These along with the Kona orange tree in the food section did not get to Hawai`i until after western contact. The thin-shelled calabash fruit, about 6" in diameter, surprisingly grow right from the bar of the tree. Calabash's gourd-like fruits were used as bowls and made into musical instruments. In this same area is the only type of bamboo early Hawaiians used and the favorite loulu palm species used for thatching.
Native Fern Garden
Our native fern garden, established recently is located next to the Pikake Pavilion. One sixth of Hawai`i's native flora is in the pteridophytes. The well-known endemic tree fern, hapu`u (Cibotium chamissoi), is commonly found in mesic to wet forests of O`ahu. Other species of hapu`u dictate at higher elevations. We are encouraging Hawai`i residents to plant the endemic tree fern in lieu of the invasive Australian tree fern that is used commonly for landscaping. In the wild, the hapu`u is threathened by feral pigs that eat the new growth; some plants were cut down for their fibrous trunk used for decoration or to mount epiphytic plants on them, such as orchids.
Ferns are a crucial part of the Hawaiian culture. In lei making, fronds are used abundantly. It is mentioned commonly in song and chant as well.