His garden covers about four hectares of lavish landscape inside soaring, glistening glass atriums at the resort, which bills itself as the largest non-gaming hotel facility in the continental U.S. There are literally hundreds of species.
"It's extremely interesting," Malone said as he took a breather from supervising his staff of 42. "It's not anything like an office with a plant or two inside."
He can stop and smell the roses, for sure. There are thousands.
When that's done, the 65-year-old horticulturist can look up at banana trees rising 18 metres above the atrium floor. For good measure, there are 12-metre-tall Southern magnolias. Not quite so imposing are two-metre-tall ginger bushes.
And that's not all. Throw in a 1,160-square-metre indoor lake, a quiet river for gondola rides and picturesque waterfalls.
But for Malone, his considerable passion has been on the plants dominating the 2,881-room hotel, which is the cornerstone of Nashville's tourism industry with one million overnight guests annually.
"I like all phases of plant life," he said. "I have a nurturing nature and I like to do things with live materials."
Water loops feed the plants with valves, controls and timers. And yes, some watering is done by hand. His staff works from 6 a.m. to 2:30 p.m., and 16 people water the plants by hand for up to 90 minutes each morning.
A climate-controlled system keeps the temperature at 20 to 22 C year round. Relative humidity stays around 55 per cent most of the time. An air exchange system ensures that air in the atriums does not become stale.
"It's kind of like a park," Malone said. "People come in and are amazed. It's always a good day inside even if the weather outside is bad."
Most of the plants rebloom "if they're happy," he said. He estimates just two per cent of the plants die.
"We've taken some out because they just got too big," Malone confessed.
The hotel, next to the Grand Ole Opry House, home of the world's most famous country music show, uses well water with very little sulphur and just a little iron. Fortunately, there is plenty of water pressure. He disdains chemicals.
"Sometimes visitors from a tropical country will come in and give me suggestions about certain plants," Malone said. "You learn."
The hotel and atriums are so far-flung that Malone, weaving through underground tunnels, was almost late for an interview on a far end of the resort. But once there, he asked the interviewer where he lives in Nashville, and a few minutes later analyzed the soil from that neighbourhood off the top of his head.
Advice for backyard gardeners:
"The biggest mistake made is buying something without thinking. You need a plan and you've got to do a little studying. Know the site and select the right plant. Making the right selection is the key. And remember that there is no such thing as no maintenance.
"Plants like warm (not hot or cold) water.
"Light is the key to everything. No light, no plant growth.
"Most people kill more plants by overwatering, not underwatering."
Donna James of Minneapolis, admiring the plants during a two-day stopover at the hotel en route to Florida, said she could use Malone's expertise in her own backyard.
"He has a pretty darn hard job, and he's done an excellent job," she said. "I don't do too well."
Malone goes home and works every day in his own garden, more than three hectares with a lot of boxwoods and quite a bit of shade, "which makes it harder."
"I'm fascinated by green things," he said.