APOPKA, Florida (AP) -- When it first sprouted, few dreamed the edifice would be the palace of a king.

Admittedly, its glass exterior sparkled the way a palace should. But it was rectangular, squat, reaching but two stories in height, and had immense, cylindrical tanks out front. Silos.

"A lot of people thought it was a museum, or a corporate office, or a chemical plant," says Nancy McDonald, who six years ago was among the first to see the structure flowering among the live oaks of this central Florida town.

It grew and grew, and grew some more, spreading 9 acres (3.6 hectares) in a single year. And as it grew, she recalls, "there were people who were saying, 'We're not going to allow it. This can't happen here."'

In the end, however -- once the locals realized that environmental rules had been followed and they saw what the mysterious troop of engineers from Holland had created -- they marveled at the latest addition to "The Foliage Capital of the World."

It was ... a greenhouse.

But no garden-variety greenhouse, to be sure. This one operated almost entirely by computer. It had robotic soil hoppers. It had an automated "Birdhouse," which monitored temperature and humidity. Its mist sprayers, its plant spacers, its retractable ceiling curtains -- all were controlled from a single keypad.

It had a state-of-the-art water recycling system, machines that fertilized plants while producing no runoff, and a cooling system that required no air conditioners, just rainwater, cardboard and fans.

Each month, this nursery would shelter and nourish millions of baby bromeliads, to be shipped to every corner of the country. Each year, it would grow enough ornamentals to cover 222 major-league-sized baseball fields.

In a few years, it would help make its operator, Paul Deroose, a very rich man, indeed.

The 43-year-old Belgian entrepreneur would come to be dubbed The King of Bromeliads -- and this citadel of reflective glass, this Titanic nursery of fuzzy, spiny, wiry infants, would truly become his palace.

Bromeliads have a reputation for resilience. Commonly known as "air plants," because of their ability to take nutrition and moisture from the atmosphere, they thrive incongruously on rock outcroppings and cactus, telephone poles and wires, even on the faces of precipitous cliffs.

They grow in virtually every kind of habitat -- deserts, cloud forests, rainforests, mountains -- and Deroose knows something about all 3,000 or so species, from Spanish Moss (neither Spanish nor moss) to Catopsis berteroniana (which traps and eats insects) -- and even the one tasty bromeliad, the pineapple.

Plants are in his roots, a fact laid bare by a family history volume that traces the Deroose tree back to 1855 Evergem, Belgium, with sepia-tone photos of his ancestors, growers all.

One snapshot shows his father, Albert, standing in the rubble of his family's greenhouse in suit and tie, with a vaguely doubtful grin commonly seen in World War II-era photographs. "During the second world war, this company was bombed three times," the caption reads.

"After the war," Deroose recalls, "my father started his own business. At first, he grew azaleas. Then he switched to bromeliads. It was totally new at that time; nobody was doing it."

Two lessons, he says, are to be drawn from his father's experience. "First, you never give up. And second, you never give up."

The tenth of 12 children, Paul Deroose went to work as a teenager for his older brother, Reginald, who by the late 1970s was running the business. New bromeliads were -- still are -- being discovered, and the brothers would go once or twice a year to the Amazon to hunt for species.

The other frontier they explored: cloning.

Not unlike what scientists do with sheep, the Derooses began making bromeliads from plant stem cells, selecting seedlings from scores of offspring and treating them with chemical cocktails.

Thorns were eliminated. Rosettes, whorls of strap-shaped, leathery leaves that form cups at the center of the bromeliad, were lengthened, curled, flattened; the hues of the central flower spike were made more brilliant, and less.

Having broadened their plant palette, the Derooses looked to expand their customer base to the United States, a particularly inviting market. There was, however, one thing holding them back:

Dirt.

The U.S. government bans imports of plants with soil on the roots, to keep out diseases and insects, so the infant bromeliads the Derooses were exporting to the United States needed always to be scrubbed free of dirt, dried, and packed in paper bundles before shipping.

This process took a heavy toll on Deroose's product: the "bare-root plants" would crack and wither. It took them as long as eight weeks to recover and grow new roots.

So, in 1994, at a tropical plant show in Florida, Deroose struck a deal with a local grower to rent a ramshackle nursery so that he could raise his bromeliads in Grade A, American soil. Within three months, he and his wife, Annick, had sold everything in Belgium and hunkered down in this sleepy town of tree farmers, soil distributors, and purveyors of pots.

Business was slow-growing at first. Plant varieties to suit American tastes had to be developed -- and breeding a hybrid takes time.

Within a few years, though, the business bloomed. The Derooses forged relationships with inventors and bromeliad discoverers, and went full bore selecting and propagating more colorful, more durable bromeliads. To date, they have created more than 2,000 varieties.

"Whenever you come up with a new one," Deroose says, "you really sleep well at night."

Today, interiorscapers and plant brokers snap up the likes of his Guzmania "Wowie Zowies," Vriesea "Towering Flames," Neoregelia "Rafaels," and the list grows by the month.

"Most bromeliads that come to market in America pass through Paul's greenhouse," says Tony Godfrey, owner of Olive Hill Greenhouses in Fallbrook, California, one of the largest bromeliad sellers in the United States.

Enthusiasts sniff at big retail outlets and go to great lengths to cultivate their own, personalized varieties, he says, but "if you're an average American and you've got a bromeliad in your home, chances are that it came from Deroose's hand."

By 2001, Deroose had raised enough money to embark on his boldest enterprise yet: the construction of a $7 million (euro5 million) nursery, described by one magazine as a work of "automation art," that would revolutionize the industry.

It has no well, and sucks not a drop from the local aquifer. Rather, it captures rainwater and condensation from the roof and stores it in four holding tanks with a capacity of 2.2 million gallons (8.3 million liters). Four inches (10 centimeters) of rain fills the system with enough to supply the nursery 131 days.)

By not using groundwater, chemicals normally used to treat the water (which can leech into the ground and contaminate aquifers) are unnecessary. And "bromeliads, like most plants, don't like groundwater anyway," Deroose says. "It's harder, full of minerals. Rainwater is fresher, tastier."

After the collected water irrigates plants, an elaborate, computerized gutter and plant-tray system sucks up runoff, stores it, and reuses it.

Pesticides and fertilizers not absorbed by the plants are recycled the same way into 30,000-gallon (113,560-liter) silos, reducing runoff and costs. "We used to buy fertilizer by the pallet," Deroose says, "now we buy it by the bag."

The greenhouse is largely cooled by recycled rainwater, which slides from the glass roof down cardboard-filter pads along the structure's outer walls. As air passes through the permeable pads it cools, naturally, without losing humidity. The system cuts the air conditioning bill, and "plants love humidity, so if we can keep it while controlling our temperature it makes for a better growing environment," Eric Kellough, Deroose's 28-year-old product manager, explains.

Robotic soil hoppers fill pots with topsoil. Other robots space and pot plants 15 at a time on aluminum "benches" so conveyor belts can whisk them about the greenhouse. Robots empty, clean, stack and deliver new benches to the greenhouse's 100 floor workers.

Two layers of retractable ceiling curtains glide back and forth, automatically, throughout the day to allow sun or give shade, as needed; overhead irrigation nozzles mist the seedlings on cue; computerized heat and humidity sensors operate by themselves.

How does this foliage factory handle hurricanes?

Since 2003 "we've lost two sheets of glass," Deroose says. His structure is built to withstand 120 mph winds.

"I've never had much use for braggers," says Deroose, but it's obvious he's proud of his greenhouse. He asserts that at least 70 percent of bromeliads sold in the United States today are produced here -- a claim that neither the Florida Nursery, Growers & Landscape Association nor the Bromeliad Society International dispute.

This year, Deroose Plants expects to make more than $10 million (euro7.5 million) by shipping starter plants to growers around the globe, up from $6 million (euro4.5 million) in 2003. There are plans to expand the greenhouse 3 acres (1.2 hectares) by 2009.

Recently, the Derooses opened a 200,000-square-foot (18,580 square meters) greenhouse and laboratory in Shanghai, China. Soaring labor costs in Belgium are an incentive to move the labwork to China, and they have their eyes on the enormous Asian market.

Anything else on Deroose's plate?

"Pineapples," he muses. "We've got somebody breeding pineapples to see if we can improve them, too."