Kamaui Aiona, director of Kahanu Garden, was perturbed. On his daily check of the property one afternoon about five years ago, he spotted a young man and an elderly woman walking off a trail, down a slippery slope. Why would they be going off the path into that area? Aiona wondered.

As he got closer, he saw the man jumping up and down, trying to knock a coconut out of a low tree with his bare hands. "I was carrying a cane knife, and I went over to help him," Aiona said. "I cut down a coconut, opened it and gave it to them to drink. It was near the end of the day, and I didn’t make small talk, like I usually do with our guests, because I was irritated that they had purposely gone off the path. They could’ve gotten hurt."

The man asked Aiona to take a picture of him and his grandmother with the ocean in the background. Aiona obliged, and the visitors thanked him and left.

Shortly after, the greeter for Kahanu’s visitor program rushed up to Aiona. "‘Did you see him?" she asked excitedly. "Did you see Leonardo DiCaprio?’"

Aiona hadn’t recognized the A-list Hollywood actor, but, he said, "I thought it was great that he had heard about Kahanu Garden and had taken the time to bring his grandmother here, because we’re a bit off the beaten path."

Indeed. Founded in 1974, Kahanu covers 464 coastal acres in the lush hamlet of Hana in East Maui. Fifty-two miles of asphalt, 54 bridges, 600 hairpin turns and dozens of scenic lookouts lie between Hana and Kahului; it has been called the most magnificent and the most challenging drive in Hawaii.

Kahanu is one of the five gardens of the nonprofit National Tropical Botanical Garden; the others are the Kampong in Florida and McBryde, Allerton and Limahulu on Kauai. The group’s mission is to discover, save and study the world’s tropical plants, and to educate the public about them.

At Kahanu, visitors can admire species from Polynesia, Melanesia and Micronesia that are valued for food, medicine, clothing, shelter, tools, rituals and adornment. The Canoe Garden spotlights the roughly 30 plants — including taro, banana, sweet potato, sugar cane and breadfruit — that were brought to Hawaii by voyagers exploring the vast Pacific more than 1,500 years ago.

"We have the largest and most diverse collection of breadfruit in the world — 120 varieties from 18 Pacific island groups, Indonesia, the Philippines and the Seychelles," said Aiona, who holds a master’s degree in Hawaiian ethnobotany. "Visitors are able to see the diversity in the shapes and textures of the plants’ leaves and fruits. We are cultivating some varieties that no longer exist in their native lands."

Breadfruit is low in fat, cholesterol and sodium and high in fiber, potassium and vitamin C. Kahanu’s collection is part of the National Tropical Botanical Garden’s Breadfruit Institute, which is studying the potential of breadfruit as a staple for undernourished tropical nations.

Kahanu also claims one of Hawaii’s largest remaining native hala (pandanus) forests. Traditional uses for hala include the making of sails, baskets, mats, fans, clothing, mattresses, pillows and footwear.

In this peaceful, pristine place, Aiona works hard to develop projects and programs that connect people to Hawaii’s history and culture and inspire a deep appreciation for nature. He conceived the idea of establishing a community garden at Kahanu, and was thrilled to see 5-acre Mahele Farm open in January last year.

"It’s based on the traditional concept of mahele, which means ‘to divide,’" Aiona said. "We invite the community to share in the work and, as a result, share the harvest. We’re growing dozens of crops, including beets, carrots, pumpkin, squash, corn, beans, papaya, eggplant, tomatoes, salad greens, ginger and many types of tropical fruit."

Twenty to 50 Hana residents farm at Mahele every week, reaping the rewards of exercising outdoors, fostering a strong community spirit, learning cultivation methods from kupuna (elders), participating in an activity everyone in their family can enjoy and gathering fresh, healthy, home-grown food.

"Kahanu Garden’s mission is based on values and goals that I cherish," Aiona said. "I love that my responsibilities run the gamut, from writing grants to designing and planting landscapes. And it all happens in an astonishingly beautiful and powerful setting."

Thick jungle peeled off to uncover Piilanihale

Kahanu Garden harbors an archaeological jewel: Piilanihale Heiau, which, measuring 570 feet long and 291 feet wide, is the largest ancient place of worship extant in Polynesia. This National Historic Landmark was built of lava rocks painstakingly fitted together without mortar.

Standing more than 50 feet high, the tallest remaining stone wall that was built in this manner in Polynesia is part of the structure’s northern face.

Scholars believe the massive heiau, whose name means "House of Piilani," was constructed in several stages, starting in the latter part of the 13th century. Its name suggests King Piilani, who united Maui under one rule, built part of the heiau or lived there, although there’s no evidence to support this. What is certain is that the heiau was built by a powerful ruler who either lived there or nearby, and that it was a sacred site designated for religious ceremonies.

Over the years, jungle encroached upon Piilanihale, eventually covering it. In 1974, Kahanu’s staff and volunteers began to clear the thick vegetation and re-stack and stabilize the heiau’s terraced retaining walls. The work was done sporadically over two decades, as people had the time.

In 1998, archaeologists from Bishop Museum and the state of Hawaii spearheaded a dedicated effort to restore Piilanihale Heiau to its full glory. The project was completed a year later.

Cheryl Chee Tsutsumi is a Honolulu-based freelance writer whose travel features for the Star-Advertiser have won multiple Society of American Travel Writers awards.