Dallas may not be celebrated for its cool green beauty, but the area around White Rock Lake, and more specifically the Arboretum and Botanical Garden, is a welcome oasis. Just 15 minutes from the gleaming skyscrapers of downtown Dallas are nearly 70 acres of carefully planted and groomed gardens and natural woodlands, interspersed with a handful of historic residences, that meander along the banks of the lake. The Jonsson Color Garden features one of the nation's largest collections of azaleas, which bloom spectacularly in spring, and nearly 6 acres of chrysanthemums in the fall. And while North Texas is not exactly New England, October and November are as ablaze in color as anything you'll see in this neck of the woods. If you find yourself in Dallas during the torrid summer (or spring and fall) months, the Palmer Fern Deli is a secluded, shady spot where mist-sprayers drop the temperature at least 10° to 15° -- reason enough for a visit here. An hour is probably enough time to see most of the gardens, though it's a fine place to linger, read, and relax.