Agriculture Reference
In-Depth Information
POLLINATION NOTES
Runner beans are outcrossers that are pollinated by insects—mainly honeybees
and bumblebees. Multiple varieties grown without isolation are very likely to cross with one another.
Small-scale home growers should use an isolation distance of at least 500 ft. (150 m), although if there
are no barriers like hedges, tall plants, or houses, 1600 ft. (500 m) is recommended. Some white-
flowered varieties are able to self-pollinate. Although it happens seldom, it is not unheard of for runner
beans to pollinate common beans. In our increasingly common hot summers, yields of runner beans
are greatly reduced, because, though runner beans flower in such heat, they produce no pods.
Runner beans have either red, white, or pink blossoms.
GROWING FOR SEED
Seeds can be sown once the ground has reached 46-50°F (8-10°C). Runner
beans are less fussy about temperature than their relative, the common bean. They love cool, wet
weather, and they thrive at high altitudes, much better than common beans. Runner beans do not
handle hot weather well, however. They are very vigorous growers that require very tall trellises,
though a few bush varieties do exist. Runner beans are perennials in their native climate but not winter
hardy, so they can be dug up, taproot and all, and overwintered in the cellar like dahlias. Plant out the
following year after the last spring frost. These plants will produce ripe fruits before first-year plants.
HARVEST
Because runner beans take longer to ripen than common beans, it is best in most climates to
reserve the first pods for the seed harvest and eat later pods fresh. It is however still recommended to
designate specific plants for seed production, because each plant stops blossoming as soon as their first
seeds ripen. Seeds can be harvested when they rattle noticeably in the dried pod, as they do with the
common bean. Seeds are in various shades of violet to reddish brown, with dark marbling and spots,
plus pure white, light green, and black.
SELECTION CHARACTERISTICS
As for common beans.
DISEASES AND PESTS
Runner beans are generally more rugged than common beans (which see), but
they are still susceptible to bean weevils and bean rust.
CULTIVATION HISTORY
The three wild subspecies of runner beans grow in cool, moist mountain re-
gions from northern Mexico to Panama at 3200-9600 ft. (1000-3000 m) elevation; here, both wild and
cultivated varieties are perennial. The runner bean came to Europe in about 1654, later than the com-
mon bean, and quickly found its way into Parisian flower bouquets and garlands. It is grown mainly in
central and northern Europe as a crop and as an ornamental, appreciated for its high resistance to dis-
ease, robustness, and adaptability; with its lower heat requirement (when compared to common beans),
