More than 2,000 species of tropical plants thrive in this little-known Eden by the sea. The 40-acre valley garden, nestled between the crashing surf and a thundering waterfall, includes torch gingers (which tower on 12-ft. stalks), a banyan canyon, an orchid garden, a banana grove, a bromeliad hill, an anthurium corner, and a golden bamboo grove, which rattles like a jungle drum in the trade winds. Some endangered Hawaiian specimens, such as the rare Gardenia remyi, flourish in this habitat. The self-guided tour takes about 90 minutes, but you’re welcome to linger. Pick up a loaner umbrella in the visitor center, where you register, so that passing showers don’t curtail your visit. Note: You enter the garden via a 500-foot-long boardwalk that descends along a verdant ravine.