Post category: Runner Beans
Although french beans are widely grown in Irish vegetable gardens, runner beans have never really caught on in the same way. Perhaps the requirement to raise the plants indoors and later to find bean poles to support the bean plants was too much trouble or, more likely, the results were not as good as expected. The runner bean, Phaseolus coccineus, is native to Mexico, growing as a scrambling climbers in scrubby land in mountainous parts where the summer temperatures are not excessive.
It is a perennial, producing large fleshy tubers at the roots, much like dahlias, but it is almost always grown as an annual, the seeds sown in spring. But it is possible to lift the tuberous roots, overwinter them in a frost-free place, as for dahlias, and plant them out the following May. This might be done as a curiosity because the young plants from seed usually possess more vigour. In some countries, runner beans are grown primarily for their flowers and seasonal shade value.
Runner beans can be finicky to grow. The plants can be slow to start growing in cool weather in early June and if they get a set-back they take a while to recover. They respond badly to cold weather, the flowers ‘running off’ without setting, and also to hot, dry weather, when the same problem occurs. However, when runner beans get the right conditions, embarrassing large quantities of beans can be produced – a freezerful!
Cooking runner beans
Runners can be used in a variety of ways – much as other kinds of green bean. Unless used very young, which is possible, they are generally too hard and crunchy to use fresh, so they are generally cooked, sliced up, by boiling or steaming for as short a time as necessary to cook them through but still leave them reasonably crisp. The cooked beans can be used cold in salads, added late to casseroles and stews, in risotto, re-heated with oil and garlic on a pan, and in myriad other ways. Runner beans are a good source of folic acid, vitamin A and vitamin C and also provide fair amounts of iron as well as dietary fibre.
Growing runner beans
Site and soil
The site needs to be warm, sheltered and sunny and the soil must be deep, rich and very fertile with lots of humus. Runner beans are very fast growers.
The old standard, still grown, is ‘Scarlet Runner’. ‘Polestar’ is a newer variety, stringless and quick to mature. ‘Red Rum’ is even newer and supposed to be even more reliable. ‘Hestia’ is a dwarf kind, which does not climb and needs no support. There is no advantage in white-flowered varieties and ‘Mergoles’ is a good example.
Runner beans are generally sown in a greenhouse in April and grown on into two-litre pots. The seeds can also be sown outdoors in May but usually do not do as well, especially in a poor summer.
Runner beans are climbers and need the support of strong canes or bean poles made into wigwam of some sort, in a row or in a circle. Space the poles about thirty to forty centimetres apart.
The young plants, usually about thirty to forty centimetres tall, are planted out in late May of early June, ideally in moist, warm weather. Delay if it is cold. Plant one or two plants at the base of each pole, tying the stems lightly until they start to climb. Water after planting.
Water runner beans during any dry spell of more than a few days.
Pick the beans as soon as they as big enough, the first when only finger-length if you wish. Regular picking keeps the plants flowering. If some bean pods begin to mature, the plant divert resources to the developing seeds at the expense of flowers and new pods.
Generally, runner beans are trouble-free, the main problem being ‘running off’ of flowers and failure to set pods. This problem, which is largely weather-related, can be lessened by providing the right site and soil conditions.