Beyond the high, clipped hedges and grand gates, private wonderlands abound. A leading creator of these Palm Beach Edens is Jorge Sánchez, a founding partner of SMI Landscape Architecture, Inc. On this American Riviera, it is a small and selective island firm for clients who dream big.

They include David Koch, who wanted a sculpture garden for his oceanside estate. He chose works by luminaries Henry Moore and Aristide Maillol. Financial maven Thomas Peterffy, another “one of our local billionaires,” according to Sánchez, wanted on his six-acre estate a rustic, classical folly for watching smoldering sunsets over the Intercoastal Waterway and a boardwalk over a mangrove swamp; it unfolds today as a private arboretum with its collection of towering trees. (He paid $22 million for the prized piece of land.) Other island clients, summer denizens of Chatham, Cape Cod, requested a courtyard garden reminiscent of the garden at the Isabella Stewart Gardner Museum in Boston, itself inspired by a Venetian palazzo garden.

With its balmy ocean breezes, sun-splashed days, and starry nights, Palm Beach is a mecca for indoor-outdoor living. Here, a space was reconfigured for entertaining with the assistance of Les Ensembles of Montreal. Beyond the pool is an old wall from Casa Bendita, a former Phipps family estate.

Sánchez is Cuban-born and his roots are in land; his family left behind some 100,000 acres in Cuba, as well as a Havana great house with signed Tiffany window, when they exited the island under Castro’s regime. Self-educated as a “landscape gardener,” as he calls himself, his conversations are punctuated with references to the great gardens of the world, which he has visited as his teaching tools. He is currently planning an office study tour of English gardens.

A contemporary Renaissance man, Sánchez authored a book last year on The Making of Three Gardens ( Merrell, $70 ), which chronicles his sublime mastery of estate planning, with projects ranging from Scarsdale, New York, to Palm Beach to Coral Gables, Miami, and the Bacardi estate there of the great-great-grandson of the rum company founder (who personally trekked around Florida in search of magnificent trees for his compound). Writing the introduction to the book, the Duke of Devonshire, who gardens at Chatsworth, his English country seat, noted that “the author is modest but clearly a master of his trade. . . . His legacy will be hugely significant.”

The sound of water was carefully calibrated to be a soft trickle; Sanchez was influenced by the gardens at the Alhambra in Spain and notes that the shoots of water one sees there today are a 19th-century addition.

In Palm Beach, Sánchez’s own home has his signature checkerboard turf panel surrounding the pool and columned loggia, and it is surrounded by a “civilized jungle,” as he calls it. Sánchez also owns an elegant ranch in the Florida hinterlands, where he retreats on weekends and conducts his botanical experiments. No greenhouses are needed in this tropical growing paradise.

Sánchez and his team have also enhanced the public beauty of Palm Beach, including making Worth Avenue—the fabled shopping street designed by Addison Mizner, bright with bouganvillea—even more pedestrian friendly. They added a living wall. A stroll away, another project, Pan’s Garden, is a haven for native Florida plantings and a quiet meditative space with uplands anchored by great live oaks and wetlands. The walled garden is a former parking lot, and a reverse twist on the song—they paved paradise and put up a parking lot.

Geometric boxwood parterres are planted with masses of lavender and white pentas, always in bloom and with a soft flow of color. This garden room overlooks a rose garden with a wishing well (not pictured); red roses include a Knock Out groundcover and Don Juan climbers.

A civilized jungle reigns at La Solana, on the beach. A central feature of the courtyard garden is the pond, where frogs spout water into the fountain, surrounded by dwarf papyrus and flanked by Solanum trees with blue blossoms.

Walking the wilds of Palm Beach, a boardwalk ribbons over the protected mangrove swamp of this six-acre estate. The mangrove is a magnet for birdlife.

A great banyan tree was growing on the estate. It joins a collection of trees that unfolds as a private tropical arboretum and includes rare kapok and baobab. Many mature trees were brought in and transplanted.

A vanishing-edge pool merges seamlessly with the Intracoastal Waterway. It is flanked by a coquina stone and turf checkerboard panel, an SMI signature. Coquina stone is mined in inland Florida.

“It’s tropical Capability Brown,” says Sanchez, referring to the legendary landscape architect for the landed gentry in 18th-century England. On this estate with its broad lawns and scattered towering trees, all tropical, a baobab tree, native to Madagascar, is pictured in the foreground and believed to be the only one growing on Palm Beach.