Are pink flamingoes still your idea of lawn and garden decor, even though we're in the dead of winter? If so, then let's face it: winter landscape design is just not your cup of tea. You'd prefer a tropical landscape design -- you just don't happen to live in the tropics. But don't let that stop you. Cold hardy palm trees do exist. In fact, The Hardiest Palms, a Web site dedicated exclusively to disseminating information on cold hardy palm trees, notes that one species of palm tree has withstood temperatures as low as -20°F!