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ONLINE DOCUMENT: PLANTING A SUCCESSFUL WINDOW BOX

Americans returning from great Britain are invariably inspired by the English flair with window boxes. Color drips from windowsills along every country lane; sumptuous foliage spills from balconies of townhouses.

Having been there, I must agree that the British have raised window box gardening to an art.Horticulturally gifted - and blessed with a benevolent climate - British gardeners work hard at their craft. But there's no magic in their magnificent color schemes, no secret pool of plants unavailable to us.

Great window boxes just take a little imagination, a willingness to experiment with plants other than red geraniums and variegated vinca vine. Attention to detail helps, too.

Follow these tips to get the creative juices flowing:

- Choose a dominate color scheme for each season. Accent with complementary or contrasting colors, but always let the primary shades read through.

- Mix and match different types of plants, not just annuals, to create sensational combinations. Consider herbs, perennials (those with a long blooming period are best), ferns, vines and tropical plants before making your choices.

- Rely on handsome foliage for texture and a long season of interest. Under close scrutiny (and window boxes are usually right at eye level), even fancy flowers can't conceal shabby leaves. Fragrant foliage (scented geraniums) and colorful leaves ("Purple Ruffles" basil) also offer attractive possibilities.

To achieve the lavish look admired in England, plant window boxes generously. Squeeze in multiple layers of plants - tall ones in the back, mounded specimens in the middle. Use spillers, creepers and cascading plants to line the outside of the box.

Reserve a few small pots of "filler," asparagus fern or baby's breath, for instance, to tuck among the others. Fillers can be added or removed as needed to give the window box that gracious overflowing look.

All of this crowding takes its toll, of course. Within a few weeks foliage and flowers will be tumbling over each other and their roots will have filled their growing space.

As the plants grow, water and fertilizer will help compensate for cramped quarters. You may notice that the boxes only need watering twice a week at first. But daily watering may soon be the only way to satisfy thirsty roots.

Incorporate water-absorbing crystals (Water Grabber, SuperSorb, AquaSorb) into the soil at planting time to reduce watering chores. And fertilize once or twice a week with a balanced soluble plant food.

Constant grooming is what keeps the window boxes in England - and those here at home - looking natural and effortless. In the beginning, pinch plants to encourage bushiness; later to remove unsightly foliage or spent blossoms.

One heavy shearing, when pinching is no longer enough, may extend the life of the planting.

Eventually, however, most window box plantings will just give out. Intense competition for root space and non-stop performance expend a lot of energy.

One by one, blooming plants will no longer respond to pinching or fertilizer. Foliage plants sometimes last a little longer, but seldom does a single grouping thrive for an entire season.

This is no cause for alarm; just a decision. Gardeners who view window boxes as a process rather than a finished product will manage their planters like small intensive plots: Cool season pansies will give way to heat-loving dwarf marigolds. Small pots of sweet alyssum will later replace dying blue lobelia. Cheery `Goldheart' ivy can stay in place; it will look nice the whole season.

Gardeners with a yen for closure will overturn the entire box and start again with a new season and new combinations in mind. Cool season annuals like daisies, snapdragons, calceolarias and calendulas - gone. In their places: ivy geraniums, tricolor sage, artemisia, lavender, parsley, `Moonbeam' coreopsis or nasturtium.

If the window box is on the shady side of the house, cascading tuberous begonias, variegated `Glacier' ivy, impatiens, ferns, coleus, caladiums and miniature hostas would be more appropriate.

Dahlias, flowering kale, chrysanthemums and deep blue plumbago will make window boxes sparkle with autumn hues. Obviously, it takes some advance planning to have pots ready to go when their turn comes.

Gardeners really serious about their window boxes can create winter charm with evergreen boughs, berried branches and elegant twigs such as corkscrew willow, winged Euonymus and wild raspberry canes.