WRITTEN BY VALERIE EASTON

	STEVE RINGMAN / THE SEATTLE TIMES FILE
	Dr. James Savage's tiny fourth-floor Capitol Hill balcony is packed in white flowers to illuminate summer evenings. Pearly clematis, white geraniums, nicotiana, roses and lilies, trimmed with silver-leafed artemisia, reflect the glow of the moon and city lights even as the sky darkens.

White's charisma lies in the fact it gives back more light than it receives with its ability to bend invisible ultraviolet and infrared light into the visible spectrum. Our black-and-white vision is a thousand times more sensitive than our color vision, thus the dichotomy of white as both an absence of color and as a powerful and reflective presence in the garden.
 

Now In Bloom Sea hollies belong to the carrot family, although you'd never guess it from the shiny, spiny leaves and architectural structure of Eryngium agavifolium. This Argentinean sea holly is drought tolerant once established, needs sunshine and good drainage, and looks more like a yucca or agave when grown into its mature-sized, 2-foot mound with 18-inch-long strappy foliage. Eryngium giganteum, or Miss Willmott's ghost (above) is grown for its silvery blue thistle-like flowers that by midsummer rise to 5 feet above a clump of spiny foliage; E. alpinum gives a similar ethereal effect on a smaller scale.

To prevent white from fading into insipidness under sunny skies, you can kindle a spark by mixing in some blue or lemon yellow, or show white off by setting it against dark-green yew or boxwood. Silver-leafed plants accent and extend the pale palette, a trick pulled off perhaps most skillfully by Vita Sackville-West in her white English garden at Sissinghurst, which more than 50 years after its creation remains one of the most admired, written about and visited gardens in the world.

The garden gives us clues about how to make the most of midsummer because it offers up plenty of white bloomers to make the most of every last drop of light. The midsummer white-fest is presaged by the bloom of white lilacs, white pulmonaria, bleeding heart and white flowering currant. And some of the most charming white flowers, like the flamboyant Casablanca lilies, white lavender and hydrangeas, are still to come as summer progresses. But it's worth pausing right now when days are longest to enjoy the opalescent veil gilding the garden, and perhaps help it along with a few more white-blooming shrubs, annuals and perennials.

The supremely sweet-scented annual flowering tobacco (Nicotiana sylvestris) drips white flowers off its sticky stalks. It grows tall and wide to fill a flower bed or large pot, its night-onset perfume strong enough to penetrate your dreams when planted by an open bedroom window. When paired with the pale, elegant double bells of angel's trumpet (Brugmansia x candida 'Double White'), the two give an exotic look to the garden, evoking the tropics to warm up our sometimes still-chilly evenings. Crambe cordifolia is one of my favorite white-flowering perennials, with its vast, cabbage-crinkled leaves and billow of tiny flowers that form a white cloud high in the air.

Indian hawthorn (Rhaphiolepis indica 'Clara' or other cultivars) are sturdy, prunable evergreen shrubs with pure-white flowers set against dark-green leaves. They're perfect for flower arranging, but regrettably unscented. This lack is easily filled with Carpenteria californica, another evergreen with large, fragrant, white anemone-like blossoms in June, any of the many mock oranges (Philadelphus), or the shiny-leafed Mexican orange (Choisya ternata). Lace these shrubs with climbing Rosa 'Iceberg' or the white potato vine (Solanum jasminoides), plant the white-flowering weaver Geranium incanum 'Album' at their feet, and you'll have a luminous garden that draws out the twilight and glows like the moon.

Valerie Easton is a Seattle free-lance writer and contributing editor for Horticulture magazine. Her e-mail address is valeaston@comcast.net.

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