The Hawaiian word "ahonui" means "patience" — a fitting name for the spectacular botanical gardens that Jason Robertson and his family have painstakingly sculpted over the past decade out of a once nearly impenetrable jungle.

In 2001 Robertson’s dad and stepmother, Bill and Lucinda Robertson, purchased the 8-acre Princeville parcel that has become Ahonui Botanical Gardens. Then residents of San Diego, they visited the site a few times a year for stays ranging from two to six weeks. They spent long hours uprooting invasive species on the property, initially wanting to just open up access to Anini Stream and other scenic spots for picnics.

Excited about the possibilities, however, Bill and Lucinda expanded their vision, and Ahonui blossomed with the help of friends, neighbors, family and horticulturist and landscape architect Michael Wise, with whom they had worked in San Diego.

In 2004 the couple decided to retire on Kauai and turn full-time attention to the gardens. The resulting oasis, notable for its diversity, has exceeded their expectations.

Jason Robertson moved to Kauai from Portland in July 2010, primarily to launch Ahonui’s marketing program and tour operations. On frequent visits over the years, he had cleared large sections and planted much of the greenery himself.

"Creating and maintaining the gardens and keeping the jungle in check is a lesson in patience," Robertson said. "There’s another level to ‘ahonui,’ which, when broken down literally, translates to ‘great breath.’ This resonates with my family, which has practiced Eastern meditation and breathing techniques for years. Our choices of plants have been influenced by our appreciation of Asian and Indian culture, and we have many specimens from those regions."

All told, more than 450 species flourish at Ahonui, and new ones are continually added. The gardens opened to the public for guided eco-tours in August 2010.

"Technically, Ahonui is our backyard, but it didn’t feel right to keep all that beauty to ourselves," Robertson said. "My dad has done a brilliant landscaping job. He has an intuitive sense about the land, and he sees layouts before the jungle is even cleared."

In the mix are native Hawaiian flora, potent medicinals, culturally significant species, alternative food plants and exotics that visitors aren’t likely to see on the mainland or even at other gardens in Hawaii. Some plants and trees were selected simply for their beauty.

Three times a week, Robertson leads visitors on walking tours, explaining the development of the gardens, sustainable practices such as making compost from green waste, and the difference between endemic and indigenous plants. He also discusses landscaping and cultivation tips; invasive species and why they are a dangerous threat; the steps that are needed to supplement Ahonui’s acidic, nutrient-poor volcanic soil; and a host of interesting plants, including the two dozen "canoe plants" that Hawaii’s first settlers brought to provide food, clothing, shelter, medicine and more.

Among other highlights is an extremely rare species of the baobab tree, Adonsonia perrieri, which is limited to perhaps 12 groves, each with fewer than 12 trees, in the wilds of northern Madagascar. Another standout is Amorphophallus titanium, recognized as the largest flower in the world, which can grow up to 10 feet tall. It’s often known as the "corpse flower" because it emits a stench akin to decaying flesh.

One of Robertson’s favorites is the horseradish tree (Moringa oleifera), nearly every part of which is edible. "It grows well in poor soils, is easy to propagate and care for, and keeps its leaves during droughts," he said. "It yields more vitamin C than oranges, more vitamin A than carrots, more iron than spinach, more potassium than bananas and more calcium and protein than milk. All that, and you can even dry the seeds and use them to filter 99 percent of natural bacteria out of water!"

No pesticides, herbicides or other chemicals are used at Ahonui, and the landscaping itself is natural, with pruning limited.

Tour participants sample an assortment of seasonal fruits, honey from Ahonui’s hives and organic chocolate made on-site with beans from the gardens’ cacao trees. "I give a brief history of chocolate, explain how it’s processed and talk about its health benefits," Robertson said. "We make our own 80 percent dark chocolate from cacao and organic sugar, and people can taste it only on our tours; we’re not making it in enough quantities to sell it yet."

According to Robertson, the feedback has been gratifying. "People who were dragged on the tour by their spouses or who had doubts about spending three hours in a garden wind up chatting with us for an hour after the tour is over," he said. "On two occasions visitors were so moved by the beauty and extent of the gardens, they broke into tears."

He and his family refer to Ahonui as a sanctuary, and indeed it exudes an aura of peace, protection and promise. "We feel a strong connection to the land through the work we’ve done," Robertson said. "Ahonui is an excellent example of people who were inspired by that spirit and strive to cultivate it by sharing it with others."

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