Lily of the Valley: These fragrant beauties have a tough-as-nails constitution that shrugs off bone-chilling temperatures. Plus, lily-of-the-valley is shade tolerant, making it a great groundcover for wooded backyards. Most commonly seen with white flowers, there are also varieties with pretty pink blooms. There’s also a variegated form with dark green leaves with white stripes. This plant is hardy to Zone 3. And they are deer resistant.