For 20 years, Una Greenaway was a weekend farmer who looked forward to being outdoors at Kuaiwi Farm, her property in Captain Cook on Hawaii island, when she wasn’t working a full-time job as an accountant for two nonprofit organizations. She quit her office job in 1999 to take care of her elderly parents and devote more time to farming.

"I retired, but I still work 40-hour weeks," Greenaway said, laughing. "There is immense satisfaction in seeing things grow and harvesting the fruits of your labor. Farming is not just my vocation, it’s my avocation."

An excellent example of an old Kona field system, Kuaiwi Farm is at the end of a bumpy, winding road in the heart of Kona coffee country. Its name refers to the rock mounds or walls that in ancient times separated the "kihapai," or areas where food was grown.

According to Greenaway, one translation of "kuaiwi" is "backbone," possibly referring to how the lines of rocks looked long ago as they extended down the slopes of Mauna Loa and Mount Hualalai. Kuaiwi could also be a metaphor alluding to agriculture as the backbone of life in pre-Western-contact Hawaii.

"At my farm, you can tell where the kuaiwi are by the ti plants," Greenaway said. "Wherever you see a line of ti, there’s a kuaiwi next to it. Hawaiians planted main crops such as taro and sweet potato in the kihapai. Supplementary crops such as ti, sugar cane and wauke, which was used to make tapa, were planted on the kuaiwi because they could grow among rocks."

Kuaiwi Farm, which Greenaway and her late first husband started in 1977, is part of a 20-acre parcel on the slopes of Mauna Loa that was formerly owned by High Chiefess Analea Keohokalole, mother of King Kalakaua and Queen Liliuokalani. Kunitaro Motomura, a Japanese immigrant who came to Hawaii island in about 1890 as a sugar cane worker, hand-cleared the land in 1900 to grow coffee.

When Greenaway acquired 5 acres of that property, she kept 2 acres of Motomura’s coffee trees. In 1982, her parents retired and moved from Southern California to become her partners in the farm. Her dad planted 100 more coffee trees on the other 3 acres.

"He was really gung-ho about it," Greenaway said. "The trees that Mr. Motomura planted don’t produce as much as our younger ones, but we feel a responsibility to take care of them because of their history."

Interspersed among the younger coffee trees are a cornucopia of crops, which visitors see up close during the two-hour tour of Kuaiwi Farm that Greenaway conducts upon request. In the mix at any given time are more than 30 kinds of fruits and vegetables: beans, beets and breadfruit; kale, corn and carrots; tea, taro and tomatoes; apple, arugula and asparagus; squash, sweet potato and Surinam cherry; lettuce, lemon and lilikoi (passion fruit).

On a stroll through the gardens, Greenaway offers samples of what’s in season. Guests are always intrigued by exotics such as wasabi, ume plum and lychee. Greenaway planted her lychee tree 15 years ago, and she was ecstatic to see it yield its first luscious fruit in June.

There’s always an ample supply of avocado, banana and macadamia nuts. "The nuts usually fall off the tree green," Greenaway said. "They turn brown, their husks split open and we pick them off the ground that way. It takes 300 pounds of pressure to crack the hard shell that surrounds the nut, but, amazingly, pigs and large dogs can do it in their jaw."

Tour participants can crack macadamias with a hand-cranked device, then pop the nuts right into their mouths. "I think macadamia nuts taste better raw than they do roasted," Greenaway said. "They’re also healthier because the omega 3 oils in them haven’t been destroyed by heat. My husband, Leon, eats sandwiches of macadamia nut butter and one of my jellies every day."

Kuaiwi Farm is certified organic — free of chemical-based herbicides and pesticides. To maintain the fertility of the soil, Greenaway practices crop rotation and makes her own compost using food waste, cacao pods, coffee branches and macadamia nut husks.

Her goal is to find a balance between growing crops for income and for a self-sustaining lifestyle. "On the tour, I emphasize the importance of growing more food in Hawaii," she said. "Eighty-five to 90 percent of the state’s food is imported. Over the years, I’ve been able to increase production on the farm, so I now grow half of the food that Leon and I eat. He says I have the best restaurant in Kona."

Greenaway makes sorbet from soursop, applesauce from mountain apples, jelly from lilikoi and jaboticaba, and drinks and marmalade from rangpur lime. After the tour, she welcomes visitors to taste a selection of these products with just-brewed coffee on the breezy lanai of her home.

"It’s all fresh, nutritious, delicious food," Greenaway said. "If visitors leave my farm with just one lesson, I hope it’s this: Take care of the land and the land will take care of you."

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