Scientists believe that smells can trigger strong memories. So it’s no surprise that Callman Au is so passionate about orchids, particularly the hanging hono­hono orchid, which has long, drooping stems rooted in a hanging pot.

It reminds him of home.

"My mother grew this kind of orchid, called the hono­hono," he said. "She had only a few plants in the backyard, and everybody in the family fell in love with it. … It has the most beautiful smell. No other orchid has that kind of fragrance."

Au, 82, is not alone in his love for the hono­hono orchid, also known as the anosmum or superbum orchid. When he displays them at the annual Kunia Orchid Society Show, which will be March 21-23, "there’s quite a few people that remember how fragrant it was, and they go crazy."

When it comes to orchids, he has an enthusiasm that’s infectious. You hear it in the lilt of his voice and see it in the twinkle in his eye. It comes naturally for the former high school agriculture teacher who later sold real estate, including homes in the Mili­lani neighborhood where he now lives.

He’ll gleefully demonstrate how he crossbreeds orchids, gently pulling apart a flower to expose the seeds and placing one inside another. He then takes it to a lab, where for a fee of $15, it will grow the seed in a sterile environment until it begins to sprout. Au will then get it back, plant it in a small pot and nurture it until it begins to bloom.

The mystery of it all is what tickles his fancy, especially since it can be a year or two before an orchid actually blooms.

"What if I brought in a dark purple one and cross it with this?" he said, gesturing toward a white orchid. "What am I going to get? I don’t know. If I have a thousand seeds, each seed, when it grows, will produce its own genes, and they’ll be all different."

When he bred one that he especially liked, he knew exactly what to do with it.

"I named it after my wife. This is the Frances Au," he said, holding up a gracefully curved stem with some flowers colored a rich pink. "It has as nice deep color. Many of the common hono­hono don’t have this deep color. Of the many plants that came about, I selected this as the best one."

He also named an orchid after his daughter Penny.

Now that Au is fully retired, his energy is focused on orchids. He spends hours every day working in his huge backyard; he has a double lot of more than 22,000 square feet, with fruit trees as well as a large lawn.

"I wanted three, four lots. I wanted to plant all kinds of stuff, but I didn’t have the money," he said.

Au has been all over the state in search of orchids, acquiring some from almost all the islands. "Because I was interested in the hono­hono, when I see one, I’d just buy it," he said. "I’d buy it, bring it home, grow it and see if I like it."

He has a 50-by-50-foot shaded enclosure that he built about 25 years to grow orchids and anthuriums. He keeps everything carefully organized, the orchid sprouts growing in small pots laid out neatly in rows on tables in one area, while the maturing orchids hang from racks, the stems drooping down, looking like the trunks of a large herd of elephants. Anthuriums grow in large pots placed below the racks of orchids.

"Anthuriums require less sunlight," Au said. "So these orchids are shading them so they’ll grow nice."

He knows exactly when his orchids are expected to bloom, so he’s well prepared for the Kunia Orchid Society Show, which he and Frances, 76, have co-chaired for the past 15 years. They oversaw the relocation of the show from the old Del Monte pineapple plantation to Lei­le­hua High School seven years ago, and the show has taken off since then.

"It was an anthurium show before," he said. "Anthuriums, you only have so many varieties. And then they decided to make it an anthurium and orchid show, a combination, because with orchids there’s a world wide of varieties. Now it has evolved into basically an orchid show."

The Aus helped develop the Kunia Orchid Society into one of the most popular orchid clubs in the islands, growing from about a dozen members to about 150 now, and putting on a show that regularly attracts more than 5,000 orchid lovers. Club members regularly visit the couple’s garden to enjoy the orchids and get a few tips on growing their own.

Au is happy to give away cuttings from his garden, and at the Kunia Orchid Society Show, his orchids will be affordable because he’s not worried about making money off his passion.

"I can make some money at this, enough to pay for my expenses, my lunch, too," he said.

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