Phaseolus coccineus
Common Names: runner bean, scarlet runner bean, Dutch runner bean,
Case knife bean, seven year bean
Family: Fabaceae/Leguminosae (bean Family)
Perennial Vine, Attracts Hummingbirds, Attracts
Butterflies , Edible Plant Flowers
Scarlet runner beans have been grown in the United States since
frontier days. Here scarlet runner beans grow along the kitchen
garden fence at the Pioneer Farm Museum in the Great Smokey
Mountains National Park.
Description
Runner beans are long, twining perennial vines that are usually
grown as annuals for their showy flowers and their edible pods and
seeds. They have thick stocky roots and their vines can reach 12 ft
(3 m) or more. The leaves are trifoliate and each leaflet is
broad-oval and 4-5 in (10-12.7 cm) long. The flowers in most
cultivars are bright scarlet red, and shaped like typical bean
family flowers with the two lowermost petals united into a "keel",
the uppermost petal modified into a hoodlike "standard", and the
lateral petals modified into spreading "wings." The flowers are
about an inch long and clustered on many-flowered racemes to 10 in
(25 cm) long. There can be as many as 20 flowers on a single
flowering stalk. The legumes (pods) range from 6-12 in (15-30 cm) in
length and the seeds are about an inch long, with 6-10 seeds per
pod. The most well known cultivar is 'Scarlet Runner' which has red
flowers and burgundy and black mottled seeds. 'Black Runner' has
intense crimson flowers and jet black seeds. 'Painted Lady' has
flowers with red standards and white wings and keels. 'White Dutch
Runner' and 'Case Knife' have white flowers and white seeds.
'Butler' and Polestar' are new stringless cultivars with very long
pods to 12 in (30.5 cm). 'Hammond's Dwarf' and 'Pickwick Dwarf' are
non-climbing bush types that mature 2-3 weeks earlier than the
running kinds.
scarlet runner beans
scarlet runner beans
Runner beans are similar to green beans (P. vulgaris), but green
beans are annuals with smaller flowers in smaller clusters and
smaller seeds in smaller pods. Also, runner beans twine clockwise
when viewed from above, whereas most other kinds of beans twine
counterclockwise. Also, when runner beans emerge from the ground,
the first growth you see is the stem and the first set of true
leaves. The cotyledons (embryonic leaves or "seed halves") of runner
beans remain underground. In most other beans the cotyledons emerge
first, and the first set of true leaves develop soon after.
Location
Runner beans are native to the high elevation mountains of Central
America. They have been domesticated for more than 2000 years by
natives of the region, but wild relatives of the runner bean still
occur in Guatemala and Mexico, where they grow in cool, partially
shaded valleys in mixed pine-oak forests.
Culture
Runner bean flowers are perfect. That means they have both male and
female parts: pollen producing stamens and pollen receiving pistils.
However they are unable to self-pollinate unless an insect "trips"
the flower by alighting on the keel, causing the stamens to come in
contact with the pistil. Hummingbirds, bumblebees and honeybees
usually do the runner bean's bidding.
Light: Full sun to partial shade.
Moisture: Runner beans need abundant water during flowering and pod
expansion.
Hardiness: USDA Zones 7 - 11. Runner beans are evergreen in the
tropics, and some cultivars don't flower until their second growing
season. Where the ground does not freeze, runner beans are
perennial, and can be expected to sprout back in spring from their
tuberous roots. In colder regions, you can dig up the roots and
store in cool, damp sand for replanting in spring. Plants that
sprout back from their roots will flower much sooner than plants
started from seed. Scarlet runner bean and other varieties commonly
available in temperate regions are usually grown as warm season
annuals and they will flower in a single growing season. Runner
beans cannot tolerate frost at all, nor will they set fruit while
temperatures are above 90ºF (32 ºC).
Propagation: Runner beans are grown from seed sown in place. Space
4-8 in (10-20 cm) apart and plant 2-3 in (5-7.6 cm) deep. Be sure to
provide a sturdy trellis, fence or pole teepee. Do not plant until
soil temperature is at least 50ºF (10 ºC).
scarlet runner bean flowers and pods
Scarlet runner bean flowers are brilliant and beautiful on their way
to becoming bean pods.
Usage
Most American gardeners grow runner beans for their showy sprays of
red or red and white flowers which are attractive to butterflies and
hummingbirds. Use the twining vines to cover a trellis or arbor. Let
them scramble with clematis, trumpet vines and morning glories.
Runner beans are more popular for food in Europe. The immature
pods are used like green beans. Their texture is a little coarser
than green beans and so they are usually sliced lengthwise before
cooking. Some consider them more flavorful than green beans. The
flowers are delicious in salads. Seeds in the shelly stage are good
to eat, but the mature beans can be dry and mealy and are not
generally consumed except by Native Americans in Central America.
They eat the starchy roots, too.
Features
Scarlet runner beans are perennial. After their first year, they
will come up and flower earlier in the season. Plant some on a back
fence or a trellis and enjoy the flowers and the hummingbirds year
after year! |
