These London window boxes signal unrealistic expectations and horticultural imperialism.

Dear Avant Gardener, I have a daughter in London who has a window box, as do most of the apartments in her area. It’s a small patch of planting that has a big visual impact. I imagine many people would be interested in advice for creating these mini-gardens. — Inspired by England

Oh, the tyranny of English gardening! The deceptively charming profusion of petunias pouring from pub window boxes! Such sublime inspiration, yet so unrealistic and even dangerous — yes, dangerous — for life everywhere. And Americans have adopted the worst and left the best back in England.

Unrealistic expectations

Why do London window boxes look so good? The weather. London gets 164 days of precipitation for a total of about 30 inches, with average summer highs of 72 degrees and winter lows of 45 degrees. It turns out this weather — which is pretty consistent throughout England — is unique. In North America, only two cities have similar climates: Seattle and Vancouver.

Window boxes benefit from London’s regular but not excessive precipitation and moderate temperatures. Their narrow, long and shallow shape produces a high ratio of surface area to volume, which means water evaporates and soil bakes or freezes much more easily than in the ground or bigger, deeper containers. In most of America, window boxes generally require harder work (watering, replanting, storing out of season) with less reward (short growing season).

Horticultural imperialism

England’s perfect weather encouraged a passion for gardening that, combined with a lack of native species (only 1,400 vs. 17,000 in the United States) led Brits to scour the world for promising plants and to breed them for beauty and long-lasting blossoms. Petunias, for example, currently the best-selling flower in England, were originally discovered in South America by a Scottish explorer and introduced at Glasgow Botanical Gardens in 1831.

By then, early Americans were already planting ornamentals from around the world, motivated by nostalgia and a desire to differentiate their yards from the wilderness around them (and their neighbors’ yards). And when American native flowers cropped up in their gardens, they dubbed them “weeds.” As a result, beautiful and ecologically valuable plants are called milkweed, ironweed, sneezeweed, butterflyweed, and Joe Pye weed.

Today, most of the wilderness is gone and American plants are rare in American nurseries. And pure species, as opposed to cultivars, are rarer still. Most people don’t realize that not only are petunias and roses and Easter lilies not native here, but neither are “wildflowers” like clover, dandelions, and Queen Anne’s lace. This is a problem because, as I’ve noted before, our ecosystem depends on insects for survival, and most of these insects depend for their survival on the plant species with which they evolved. 

None of the fun

Unfortunately, the joy of gardening did not cross the pond in such profusion. Landscape designer Claire Jones, who organizes tours of British gardens for Americans, points out that the Royal Horticultural Society has 500,000 members whereas the Americans Horticultural Society has only 20,000 — about one hundredth as many on a per capita basis. Jones explains:

One big difference between English and American gardens is how the American perceives the garden as a status symbol and the English native sees the garden more as an enjoyable oasis to putter around in. . . . The British are all about the love of gardening and being horticulturalists. Americans are more about “curb appeal” and how their yard will appear to the neighbors. — The Garden Diaries

The English call their home landscapes “gardens,” whereas we call ours “yards.” Vaguely inspired by the grounds of English manor houses, not their ornamental gardens, we cover our yards in lawn and outsource their care when feasible to “mow and blow” crews. Unfortunately, not only does lawn care not give us joy, but European and Eurasian turf grasses (no, Kentucky blue grass is not from Kentucky) often require more water, fossil fuels, fertilizer, and pesticides and provide little ecosystem value compared to the ornamental gardens more popular in England.

Back to window boxes

So, what do I have to say about window boxes? I personally only had success with them when, long ago on a Manhattan rooftop, I planted petunias. My more ecologically and agriculturally ambitious attempts have been dismal failures, leaving me with unsightly boxes of dirt most of the year. So I have abandoned them. But I am a lazy gardener and I now have more room to play.

If you only have space for a window box and want to give it a try, I encourage you to plant whatever gives you joy. The trailing annuals bred for long-flowering and sold in nurseries in your area will be easiest — petunias, fuchsias, hanging geraniums, for example. Be prepared to water frequently, swap out plants when they fail, and dress up or store your boxes during the cold season.

If you have the time and energy, do consider planting natives for their ecological value. See links below for specific container plant ideas for regions around the country.

Cheerio!

— The Avant Gardener

Why, How, Wow!

Why?

In the United Kingdom, large landowners are leading the biodiversity initiative, which they call “rewilding.” I found it funny that a headline in the Guardian reads “Rewilding ‘not just for toffs.’” According to the article, one in five councils (government social service institutions) are undertaking rewilding efforts; these councils are themselves among the largest landowners in the country.

The US effort is, typically, more fragmented. I am especially motivated by Doug Tallamy’s ambitious effort to mobilize individuals to transform 20 million acres of lawn into sustainable landscapes, called Homegrown National Park. It emphasizes that each of us can contribute to reversing biodiversity loss.

Expect conservation to gain attention this month as representatives of countries around the world meet in Montreal for the United Nations biodiversity summit, called COP15.

This is the moment we've all been waiting for — for world leaders to finally come together and agree on the next decade of conservation targets and take actions to reverse biodiversity loss to protect and preserve our life on Earth. — Margaret Kuhlow, WWF International in Reuters

How

Even if you only have room for a window box, you can participate in reversing biodiversity loss by planting natives. Here are container plant suggestions from leading native plant organizations around the country, from east to west:

• East Coast: Best Native Plants for Containers (class on demand), Mt Cuba Center 

• Florida: Create a Pollinator Pot, Florida Wildflower Foundation

• Midwest: Container Gardening with Native Plants, Missouri Botanical Garden

• Texas: Plant and Parcel, Lady Bird Johnson Wildflower Center 

• Pacific Northwest: How to Grow Pacific NW Native Plants in Outdoor Containers, Real Gardens Grow Natives

• California: Patio and Container Gardens, California Native Plant Society

Wow!

Window boxes can truly nurture nature. Author Melissa Caughey found this nest in her window box on Cape Cod in Massachusetts.

Related Resources

• Wonder how the American obsession with lawns came here from England? Read my column on lawn replacements.

• Curious about the UK’s rewilding movement? Go to Rewilding Britain.

• Interested in learning more about the global biodiversity crisis? See the UN’s Facts About the Nature Crisis.