Green Gardening: Low on water? These plants don’t mind (Google / Seattlepi)

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Green Gardening: Low on water? These plants don’t mind

By ANN LOVEJOY
SPECIAL TO THE P-I

Quite a few readers are asking for advice about plants that thrive in dry gardens. These easy-care gardens can look terrific all year, especially when filled with drought-tolerant plants that need very little help to be beautiful. By choosing evergreen plants with plenty of natural architecture, we can create boldly dramatic vignettes that hold their looks over time. Dry gardens originally were designed in a part of England that is quite similar to the maritime Northwest. Essex gardeners also contend with heavy, nutrient-rich clay soils and low summer rainfall, as well as wet and windy winters. Most dry gardens involve topography; generously scaled, mounded beds that keep plant roots out of the soggy, root-killing clay come winter. That same clay retains water well in summer, offering deep roots nutrients during the dry months.

To keep the mounds well filled, most are planted with an attractive mixture of evergreens. Selected shrubs and sub-shrubs are the usual anchors for flowing drifts of grasses and perennials. I often use shrubby hebes for their firm, rather formal shapes, from the boxwoodlike green mounds of ‘Margery Fish’ to the purple-edged ‘Mrs. Winder.’

Upright Hebe cupressoides looks like a miniature cypress tree, though the form called ‘Boughton Dome’ has a pleasingly rounded natural shape. All grow to 3 to 5 feet high and wide over time, with fine-textured leaves, and all produce little fizzy flowers at the twig tips in shades of blue or white.

Smaller hebes with lasting looks include ‘Clear Skies,’ a lilac-flowered, silvery mounder with blue flowers that reaches 2 feet, and little ‘Coed,’ with glossy green leaves and clear violet flowers. I often use carpeting Hebe pinguifolia for its grey-green leaves and puffy white flowers (bees love them).

The culinary herb clan offers a wide range of really tough evergreen sub-shrubs in a good range of colors and textures.

Though purple sage can be mysteriously hard to please — thriving here, and dying off by inches a few feet away — a large-leaved, silvery sage called ‘Berggarten’ is handsome and long lasting. It produces large spikes of blue flowers in early summer and, like the rest of us, spreads a little wider every year.

I often recommend rosemaries, because they are handsome, shapely, fragrant, edible, beloved of bees, and pretty much effortless. Good taller forms include ‘Miss Jessups Upright,’ ‘Tuscan Blue’ and ‘Beneden Blue,’ all columnar forms from 4 to 6 feet high. For a more undulating shape, consider the arching, wide-spreading ‘Severn Sea’ or ground-covering ‘Irene.’ Creeping rosemaries are less hardy than the uprights, but a light winter covering of evergreen boughs usually offers reliable protection.

Oreganos are classic dry-land ground covers and make lovely flowering accents amid wind-tossed grasses. Among the most ornamental oreganos are the tall ‘Hopley’s Purple,’ rosy ‘Rosenkuppel’ and dusky purple ‘Herrenhausen.’ Thymes, marjorams and catmint (Nepeta) are classic carpeters as well.

Use plenty of clumping grasses, avoiding runners completely. Mexican feather grass (Nasella tenuissima) makes a gilded spill, while coppery pheasant tail grass (Anemathele lessoniana) forms a shimmering fountain that holds raindrops delightfully in winter. Many of the great Carex clan work well, from the coffee-colored ‘Cappuccino’ to bronze-red Carex testacea.

Where room allows, place a great sheaf of New Zealand toetoe to be backlit by afternoon sun. This evergreen pampas grass (Cortaderia fulvida) holds stiff silvery plumes above arching, deep green foliage. Upright moor grasses (Molinia, Sesleria) make powerful accents, forming rippling, fluid fans among lower growers. Giant moor grass, M. Skyracer, is especially dramatic in a larger setting, while variegated moor grass works beautifully in compact spaces. Upstanding maiden grasses are also good choices, notably the graceful Miscanthus sinense ‘Graziella’ and shimmering, columnar ‘Morning Light.’

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Ann Lovejoy is the author of many gardening books. She can be reached via mail at: 8959 Battlepoint Drive N.E., Bainbridge Island, WA 98110.

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.