Today is World Water Day, a day designated by the United Nations to focus our attention on the importance of water. This year’s theme, Nature for Water, explores nature-based solutions to water challenges. While we can’t, as individuals, plant a forest, reconnect rivers to floodplains, or restore a wetland, there are many things gardeners can do to help.
One way – an easy way – is to replace moisture-loving perennials with perennials that are less thirsty and able to withstand short periods of drought without supplemental watering. Here are a few of my favorite drought-tolerant flowering perennials.
Achillea ‘Strawberry Seduction’ grows up to 2 feet tall and wide. It shows off bright rosy-pink flattened clusters of flowers all summer long over fern-like foliage. Plant yarrow, as it is commonly called, in well-drained soil in a spot where it can bask in the sunlight. Newer cultivars, like the Seduction series, have strong stems that don’t flop under the weight of their flowers.
Other popular cultivars of yarrow include A. ‘Coronation Gold’ and A. ‘Moonshine’. Coronation Gold grows up to 3 feet tall and sports golden yellow blooms; Moonshine displays bright yellow flowers on 2-foot stems. Butterflies love yarrow almost as much as gardeners!
Another sun-worshipper adored by butterflies, especially monarchs, is Asclepias tuberosa, or butterfly weed. This Illinois native sends down a taproot, enabling it to take up water from deep in the ground, while the plant above reaches up to 30 inches. Its bright orange flowers demand attention in the summer garden.
Baptisia australis, another native, grows 3 to 4 feet tall and wide. It, like butterfly weed, has a deep taproot – the source for its drought tolerance. Commonly called false blue indigo, it features blue flowers resembling lupines in spring that turn to large, black seed pods later in summer. Plant it in full sun to light shade. I love the way their stems emerge from the soil, looking a little like asparagus.
There are many lovely cultivars of false blue indigo including B. ‘Wayne’s World’, B. ‘Lemon Meringue’ and B. ‘Purple Smoke’. Wayne’s World is tall – up to 4 feet – and may be the best white-flowering cultivar. As you probably guessed, Lemon Meringue boasts lemony-yellow flowers on 3-foot stems. Purple Smoke also grows 3 feet tall, but blooms in lavender.
Coreopsis verticillata ‘Zagreb’ is a must-have in my sunny perennial borders for several reasons in addition to its drought tolerance. First, bright yellow, daisy-like flowers cover the plant in May and June and continue to bloom throughout the summer. Next, plants grow just 18 inches tall, perfect for the front of borders. Finally, the plant’s fine foliage provides textural contrast with larger-leaved perennials.
Other worthy threadleaf coreopis cultivars include C. ‘Cosmic Eye’ (yellow flowers with burgundy centers), C. ‘Crème Brulee’ (butter yellow blooms), C. ‘Mercury Rising’ (red flowers) and C. UpTick™ ‘Cream’ (creamy white flowers).
What would a summer garden be without coneflowers? Echinancea purpurea is an Illinois native found growing in meadows and prairies. Coneflowers hold purplish-pink, daisy-like flowers at the top of sturdy, 2- to 4-foot stems. Although they prefer full sun, they grow satisfactorily in part shade.
There are many cultivars of E. purpurea ranging in color from white to yellow to orange and pink to red. Bees and butterflies love their flowers in summer; birds love their seed heads in winter.
Becky is a buxom beauty, larger than most other Shasta daisy cultivars. Her stiff 3-foot stems never need staking. Sparkling white daisies bloom from mid-summer into fall. Plant Leucanthemum x superbum ‘Becky’ in full sun in well-drained soil.
If Becky is too tall for a position in your garden, try L. ‘Snowcap’. It grows just 18 inches tall.
Nepeta ‘Purrsian Blue’ has become one of my favorite catmints. Lavender-blue spikes of flowers bloom and bloom and bloom. N. ‘Purrsian Blue’ grows up to 18 inches tall and 24 inches wide. Plant catmints in full sun and well-drained soil.
If you love catmints but want a taller plant, try N. ‘Six Hills Giant’. It grows up to 3 feet tall and wide. N. ‘Walker’s Low’ will satisfy gardeners who need something mid-sized.
Russian sage, botanically known as Perovskia atriplicifolia, is a great choice for drought-tolerant perennial borders. Small gray-green leaves on tall silvery-gray stems reach up to 4 feet tall, presenting lavender-blue flowers from mid-summer into fall. Russian sage must have well-drained soil and full sun.
If Perovskia atriplicifolia is too tall, try P. ‘Little Spire’. A compact version of Russian sage, it grows just 2 feet tall.
Stonecrops are some of the best perennials for sunny and dry conditions. Sedum ‘Autumn Joy’ is an oldie, but goodie. Rosy-pink flat-topped flower clusters bloom on 2-foot mounds of fleshy foliage in late summer into fall.
S. ‘Vera Jameson’ grows 12 inches tall and shows off purplish foliage. S. ‘Dragon’s Blood’ and S. ‘Angelina’ both grow just 4 inches tall, ideal for ground covers. Dragon’s Blood has purplish-red foliage; Angelina features bright golden needle-like foliage.
If gardeners have a landscape full of mature trees, there are plenty of perennials that can handle drought every bit as good as they sun-loving counterparts. Here are just a few.
Brunnera macrophylla, or false forget-me-not, is gorgeous in the dry, shady gardens at my house. It grows up to 18 inches tall with large, heart-shaped, dark green leaves that spread into a lovely, weed-choking colony. Masses of small, blue, forget-me-not-like flowers cover the foliage in spring.
There is a variegated cultivar, B. ‘Jack Frost’, that is similar in size but has silver leaves with a thin green margin and green veining.
Bleeding hearts, or Dicentra spectabilis, stop visitors in their tracks in springtime. Cherry pink heart-shaped flowers dangle like jewels from long arching stems. It grows 2 to 3 feet tall. Bleeding hearts go dormant in mid-summer, completely disappearing from the garden.
Epimedium sulphureum, commonly called barrenwort, grows up to a foot tall in optimum conditions, but in my shade garden where rainfall is quickly sucked up by the roots of silver maples, it’s barely 6 inches tall. It slowly grows to form a ground cover, and bright yellow flowers rise from the foliage in spring. New leaves emerge tinted red in the spring, turn green for the summer and become red again in the fall.
Bigroot geraniums are one of best perennials for dry conditions in a partly-shaded garden. Geranium macrorrhizum slowly spreads to form a dense carpet of fuzzy, deeply lobed, gray-green leaves that turn beautiful shades of reddish-orange in the fall. Small, purplish-pink flowers bloom in late spring to early summer and continue sporadically through the summer.
G. ‘Bevan’s Variety’ has dark magenta flowers with red sepals; the blooms of G. ‘Ingwersen’s Variety’ are soft pink.
Hellebores (Helleborus orientalis) are one of my favorite perennials for the shade. They bloom in early spring alongside tulips and daffodils in shades of white, cream, yellow, green, pink, purple and red. There are cultivars with single and double flowers. Plants grow 12 to 18 inches tall.
Pulmonaria longifolia, commonly called long-leafed lungwort, grows best in well-drained soil that been amended with lots of organic matter in part shade where it will spread slowly. Its silver-spotted leaves grow up to 12 inches long. Bell-shaped purple-blue flowers appear in early spring.
Pulmonaria longifolia subsp. cevennensis features extremely long leaves – up to 24 inches long – and dark violet blue flowers. P. ‘Raspberry Splash’ shows off bright raspberry-colored flowers; P. ‘Bertram Anderson’ displays deep blue flowers.
These are just a sampling of perennials that help gardeners save water in the landscape. In the spirit of World Water Day, let’s all pledge to plant more drought-tolerant perennials in our gardens this year. It’s the least we can do.
Garden with me!