Going beyond the traditional window-box garden

The gardening world has a tried-and-true formula for the perfect window box: a thriller, a filler and a spiller. You simply can’t go wrong with a tall red geranium amid a tranquil bed of white impatiens and cascading vines of ivy.

But maybe you’re an experienced window box gardener looking to try something different. Or maybe you’re sticking close to home this spring and summer and you need a new pandemic project. How about a window box filled with succulents like aloes and echeverias, or edibles like herbs and nasturtiums, or even carnivorous varieties like Venus fly traps and pitcher plants?

Whether you’re a newbie or an old hand, here are some expert tips on window-box basics, as well as ideas for unusual themes.

LIGHT AND WATER

Before choosing plants, evaluate your window box location for light and moisture. Window boxes dry out faster than in-ground plants, so they need a lot of watering, especially if south-facing. But a window box flush against an exterior wall may be more sheltered from rain than a flowerbed in your yard.

Browne says one of her greatest triumphs as a gardener is a beautiful window box in a north-facing, fullshade spot. She gets a lush, full look using coleus, caladium and oxalis, which all have foliage in burgundies and greens with interesting patterns and shapes. Sweet potato vines serve as spillers.

How about succulents? They do best in south- or west-facing windows, according to Matthew Pottage, curator of the Royal Horticultural Society Garden Wisley in Surrey, England. His window box full of drought-tolerant plants has “survived the wet and cold of London for some seven years.”

THE WOW FACTOR

What gives some window boxes their “wow” factor while others are just so-so? Maintenance is part of the difference, says Benoit. “People who have really nice window boxes are cutting off dead, spent leaves and blooms,” Benoit said. They’re also watering a lot and

“changing things up a lot. Some plants are only going to look good for one season.”

That means replacing spring tulips and hyacinths with petunias and zinnias in summer, followed by mums and flowering kale come fall. And don’t let quick-growing plants like coleus and impatiens get too leggy.

To remedy window-box blahs, Benoit offers this hack: Take a bright cut flower from your backyard or a florist’s bouquet, insert the stem in a slender tube filled with water, and tuck it in amid your window box plants.