Salvia Greggii is one of the most reliable and easy-to-grow drought-tolerant perennials. There are many varieties of the species available and bloom colors range from pure white to pink, to coral, to deep red. As plants become semi-woody, they are often used as small shrubs in warm climates. Plants can grow approximately 3 feet tall and spread to 5 feet wide. Autumn sage begins blooming in early spring and continues until a hard frost.
AS A GROUP, SEDUMS can be relied upon to be sturdy performers in hot and dry landscapes. These hardy succulents are available in assorted sizes, shapes and foliage colors. ‘Blue Spruce’ is a variety particularly good for use as a low-maintenance groundcover along sidewalks, driveways, retaining walls and containers. This variety offers up a unique silvery-blue foliage color. Plants require a full sun location with well-draining soil. Once established, plants require little supplemental water and are highly tolerant of reflected heat.
KNOWN AS ONE OF THE MOST POPULAR culinary herbs, rosemary also performs as a lush, evergreen landscape shrub or cascading trailer. Plants are drought-hardy once established and very tolerant of the intense reflected heat. Can be used in very low-maintenance plantings without supplemental irrigation.
THIS STUNNINGLY BEAUTIFUL “BULB” also happens to be one of the most reliable drought-tolerant garden plants. The large rhizomes produced by bearded iris plants allow them to not only survive, but thrive under extended periods of drought. Once established, bearded iris do not require supplemental water. However, a bit of supplemental water now and then will result in more flowers.
UNLIKE BEARDED IRIS, IRIS PSUEDACORUS is a water-lover. Yellow flag is used to clean waterways as absorbs heavy metals. Plants can spread aggressively, creating dense clumps of foliage. However, when planted in rain gardens that periodically dry out, their spread will be slowed. Plants produce bright yellow blooms in spring or summer atop sword-like foliage.
AS WITH MANY PLANTS well-suited to a rain garden, Gooseneck Loosestrife, Lysimachia clethroids, can be an aggressive spreader depending on your location. However, if you have room to spare, they make quite an impressive display. Their long racemes of small with flowers curve as they mature, creating a gooseneck-like appearance. Plants establish easily in the rain garden and perform best in moist to wet soils.
SOME PLANTS HAVE THE ABILITY to perform double duty in the landscape by tolerating both drought and wet conditions. Maiden grass, a species in the genus Miscanthus, have that ability. This makes them perfect for use in rain gardens that may experience big swings from very wet to very dry and back again. There are many varieties available that offer up different foliage types, colors and plant sizes.