Help ensure that your garden can ride out the vagaries of weather by including plants that handle a wide range of conditions. Daylilies have sometimes been called the "perfect perennial." Low maintenance, heat tolerant and pest resistant, they put up with a wide range of soil types and light conditions, and each variety produces at least a week's worth of prolific blooms. They don't mind occasionally having wet feet and, once established, they're resistant to drought. Extreme dryness may cause them to go dormant, but they usually recover. USDA Zones 3 to 10.