Hawaii's garden isle

Kauai, like its sister Hawaiian islands, is a botanical bonanza. Bathed in the island's natural steroids of endless sunshine and warm-rain cloudbursts, plants flourish. Wandering through one botanical garden I gaped at a croton, a broad-leaved tropical plant, that towered over my head; my houseplant version had shriveled and died when it was barely 6 inches tall.

Almost anything can, and does, grow in Kauai in the wild and in its botanical and home gardens. The island's lusher north and east sides are a kaleidoscope of luxuriant ferns, rope-thick vines, lacy orchids and shimmering flowers, mango and guava trees, and stately Cook pines, almost 200 feet tall.

Kauai lives up to its Garden Isle nickname in offering some of Hawaii's best and most atmospheric botanical gardens. Some go for the splashy, colorful tropical plants; others are dedicated to showcasing and preserving native Hawaiian plants, many of which are disappearing in the wild.

That's the dark side of Hawaii's verdant beauty. Most of the showy flowers and trees -- plumeria, bougainvillea, many palm trees, even orchids -- that are considered typically Hawaiian have been brought by people to the islands from elsewhere. Some of these introduced plants (such as guava and African tulip trees) grow like weeds, choking out the native plants. Here are my favorite botanical gardens on Kauai:

Limahuli

Tucked away on Kauai's North Shore, Limahuli Garden and Preserve is the island's don't-miss garden for anyone interested in native plants, Hawaiian history and tropical scenery. The garden's setting is the stuff of fantasies, nestled into a narrow valley beneath greenery-draped rock spires that served as the Bali Hai backdrop in the movie "South Pacific."

Limahuli, a unit of the National Tropical Botanical Garden, covers almost 1,000 acres, much of it restricted for research and preservation. But visitors can walk a ¾-mile hillside trail that winds through a demonstration garden on self-guided or guided tours.

Start at the ancient rock terraces, built at Limahuli about 700 years ago by early Hawaiians to cultivate taro, their most important crop. Walk onward among plants that originally were brought to the islands by Polynesian migrants (the first of such canoe voyagers are believed to have arrived around 200 A.D.). They brought with them the plants that sustained their lives: ti plants, whose waxy leaves were used for everything from wrapping food to thatching houses; banana trees; coconut palms and more.

Keep walking into what's called the plantation-era garden, showing plants that people brought to Hawaii 200 years ago -- from pineapple and papaya to gardenias, orchids and heliconia. Considered typically Hawaiian, they're actually classified as "modern introductions" and are among the more than 10,000 species of plants estimated to have been brought to Hawaii since Captain Cook arrived in 1778. Introduced trees -- including guava, mango and umbrella trees -- have flourished in Kauai and the other islands, choking out native Hawaiian forests.

Limahuli works to restore native habitat and preserve rare Hawaiian plants. Watch for mamaki, a nettle used for tea and medicine, and loulu, a fan-shaped palm native to Hawaii.

Na 'Aina Kai

For something completely different, head to the sprawling and colorful Na 'Aina Kai Botanical Gardens, also on Kauai's North Shore.

About 100 bronze statues are scattered through Na 'Aina Kai's 240 acres; many are life-size, Norman Rockwell-esque sculptures of people. There's a meandering lagoon and woodland trails, a Japanese teahouse and waterfall; and a sprawling garden-hedge maze. For kids, there's a play garden, with a water-spray area, climbing frames, mock caves and more.

Allerton, McBryde gardens

On the southern end of Kauai, two side-by-side gardens can easily absorb a full day.

The 80-acre Allerton Garden is tucked into a valley opening to the sea. Bought in the 1930s by Robert Allerton, heir of a Chicago industrial family, and developed into a series of garden rooms, it's a romantic and tranquil enclave. Ferns cloak ravines and bougainvillea spills down cliffs; palms stretch overhead; bamboo and fruit trees flourish. The above-ground roots of Moreton Bay fig trees undulate along a stream; the almost waist-high, otherworldly fins of wood were in scenes in the film "Jurassic Park." Walk onward to a reflecting pool and mini-pavilion, a European-garden-style oasis shaded by tropical trees. The Allerton Garden can be visited only by reservation on guided tours.

The McBryde Garden, up the valley and along a meandering stream from Allerton, once was 171 acres of sugar cane and cliffs. Since the 1970s it's been turned into a garden of tropical delights, now with one of the world's largest collections of native Hawaiian plants.

The McBryde Garden can be visited at your own pace. Walk the mile of mostly unpaved paths. Take your time, and stop to smell the tropical flowers.