If there were a prize for the most versatile vegetable, the scarlet runner bean would be a serious contender, even though it’s hardly a garden staple. It may be best known as a children’s plant.
Kids are often encouraged to make a tepee out of bean poles and sow scarlet runners at the base of each. This is a great project for a small gardener — the seeds are easy to plant, quick to sprout and fast-growing. By midsummer a tent of dark green vines has magically appeared, adorned with clusters of scarlet flowers, a secret hideout of his or her own creation.
Because of its beauty, the plant has caught on in the adult world too. It makes a gorgeous screen for privacy, for camouflage, or as a leafy ceiling over an outdoor seating area. It gratifies almost instantly, while you are waiting the three years it takes for your clematis to ascend, or five for your climbing hydrangea. It doesn’t close its blooms on cloudy days the way morning glories do.
If you don’t find this scarlet runner bean in the “flower” or “ornamental vine” sections of a seed catalog, you might check under “hummingbird plants.” It’s sure to attract these hovering bits of living jewelry, who are drawn to red blossoms. It lures hummingbird moths as well. (These day-fliers buzz while they feed and are often mistaken for hummingbirds.)
Bees also are enticed — a good thing, since runner beans require their services. Unlike most beans, they are not self-pollinating.
The pollination quirk is not the only thing that sets runners apart. Most vining beans twine counter-clockwise around a support, when viewed from above (or “anti-clockwise” as the English call it). Runner beans go clockwise. They also germinate differently, forming their cotyledons (first leaflike structures) beneath the soil instead of above.
Unlike other garden beans they’re perennial in frost-free climates, forming enlarged tuberous roots. Originally from the mountains of Central America, they were first brought to Spain, then travelled widely. Though related to the familiar pole and bush beans, they constitute their own species, P. coccineus. The Latin name means “red”, but not all are scarlet. Some have white flowers, and those of the bicolored Painted Lady are red and white. The exquisite Sunset is pale salmon-pink.
Most American gardeners don’t realize that runner beans are edible, even though it has long been a culinary favorite in the British Isles. The 1969 Oxford Book of Food Plants described it as “by far the most popular green bean in Britain.” There the pods are harvested young, when the seeds are just starting to swell, and cut into short lengths, or “frenched” by slicing them lengthwise. They are then boiled or sautéed and served, deliciously, with bacon or butter. Their flavor is more satisfyingly beany than the standard green bean, especially in the old-fashioned varieties, although the modern ones tend to have more tender, smooth, stringless pods which hold longer on the vine before they swell.
Runner bean seeds are tasty too — and handsome. Those of the classic scarlet runner are purplish-black, streaked with magenta. White-flowering ones like Dutch White have white seeds and the orange-flowered Dark Coat has black ones.
For most gardeners it is simplest to sow them in fertile, moist, well-drained soil, rich in organic matter. They’ll need something to support them, unless you pinch them back to keep them low-growing, or choose one of the dwarf varieties. All of them flower and form pods better in cool weather, though some are more heat-resistant than others.
It’s not too late to poke in a few runner bean seeds if flowers are your goal. These too are — you guessed it — edible, and if you can imagine a flower tasting lightly beanish, these do. They are splendid as garnishes, or in salads. It’s quite possible that you already have some growing for your kids, your hummingbirds, or for you, and while you might not have planned it this way, the kitchen awaits them.