Seeking respite from the sun in the verdant interiors of St. Lucia, St. Vincent, and Dominica, Suketu Mehta finds that there's more to the Caribbean than slathering on the sunblock and baking on the beach. Amid blissful breezes, thermal springs, and thunderous waterfalls, he roots out the secrets long hidden in the rain forest

There are islands in the Caribbean that live in the color green. From the air you see them: big clumps of green in a blue sea. If you lie on the ground and look up at the blue sky, the view is mediated by the green of the foliage. The green is reflected in the pools that form under the waterfalls and in the moss and lichen, which grow instantly on every surface. Even many of the walls of the houses are painted a pale green. After a prolonged spell in these islands, you notice that the drinks, crowned with limes, and the food, like the soup made of callaloo leaves, are aspects of the overall greenness. It is a vivid, vibrant color, as different from the browns and dull grays of cities in the Northeast as from the endless blue that dominates the flatter Caribbean islands. It is a green that has a life of its own, and I noticed it as soon as I got out of the airport, with pleasure: The leaves are broader and greener than any I'd ever seen.

I had spent several months on an exhausting, and exhaustively scheduled, book tour, and I welcomed the chance to escape to a land that seemed beyond time. In the Caribbean, part of that timelessness is the greenery, which is year-round. I wanted to go to a place where the trees never lose all their leaves. So over several days, I traveled the islands of St. Lucia, St. Vincent, and Dominica—especially enjoying Dominica, the greenest isle in the Caribbean. I wanted to see the part of the Caribbean that most tourists overlook—the hills, rain forests, rivers, and waterfalls beyond the beaches. I wanted to see how each of these countries balances development with preserving the environment. I was fascinated by the legends, traditions, and environmental practices of the Carib Indians, and wanted to see how they live today. I also had a quest: to find one perfect waterfall to plunge into.

The Edmund rain Forest Trail crosses St. Lucia west to east and traverses streams, ravines, and hills with views over the island. I took it one morning in the capable company of Rhikkie Alexander, who used to be the forestry official in charge of this area, then became a senator, and now consults on environmental projects and gives customized tours of the rain forest. On the way up, we passed a village of Rastafarians in the hills. "What do they farm up here?" I asked.

"They practice alternative agriculture," said Rhikkie, raising his eyebrows. "Organic farming…?" I started to ask before I got it.

In the rain forest, every tree has a story or a myth or a proverb. The chatagnier—similar to the chestnut tree—is known for its huge, well-spaced buttresses. Rhikkie stopped at the base of a great specimen; at least a hundred feet tall, it has another fifty feet to go before it equals the island's tallest. The St. Lucia parrot feeds on its shoots and fruits. Rhikkie pointed out its twisted roots as holding a lesson for couples: "Buttress also means anchorage. It is an anchorage of two souls, two bodies, two minds." And he pointed out the spaces between the buttresses. "But the species also provides plenty of breathing space." No wonder there's a sign at the airport offering a stamped certificate from the St. Lucian government to couples who honeymoon here.