How to Grow Runner Beans

Overview

Runner beans are a quintessential allotment crop, producing masses of long, flat pods from midsummer until the first frosts. Their attractive red or white flowers also make them a decorative addition to any garden. A well-tended row of runner beans can easily feed a family throughout the summer.

Health Benefits

Excellent plant-based protein: Runner beans are a great source of protein, making them especially valuable for vegetarian and vegan diets alongside their generous fibre content.

Iron and folate: Rich in iron (important for energy and preventing anaemia) and folate (essential for cell growth and particularly important during pregnancy).

Vitamin C in fresh pods: Freshly picked runner beans contain Vitamin C, which is best preserved by eating them soon after harvest, another great reason to grow your own.

Soil Preparation

Runner beans need rich, moisture-retentive soil to support their vigorous growth. Dig a trench the previous autumn and fill it with kitchen waste, newspaper, and compost, then cover with soil. This creates a moisture reservoir. The ideal pH is 6.0 to 7.0. Beans fix their own nitrogen, so avoid excessive nitrogen fertilisers.

Sowing & Planting

Sow seeds indoors from April in deep pots, one seed per pot. Alternatively, sow directly outdoors in May to June once the risk of frost has passed. Plant at the base of a support structure, spacing 15cm apart in double rows 60cm apart. Erect a frame of 2.4m bamboo canes in a wigwam or A-frame arrangement before planting.

Care & Maintenance

Water generously, especially once flowering begins, as dry conditions cause flowers to drop without setting pods. Mulch around the base to conserve moisture. Pinch out the growing tips when plants reach the top of their supports to encourage bushier growth and more pods. Misting the flowers can aid pollination in hot weather.

Harvesting

Pick pods regularly when they are 15-20cm long and before the beans inside begin to swell and become stringy. Harvest every few days from July to October to encourage continued production. At the end of the season, leave a few pods to mature fully on the plant and save the dried beans as seed for next year.

Common Problems

Flower drop without pod set is common in hot, dry weather. Keep plants well-watered and try misting flowers to aid pollination.

Blackfly (black bean aphid) clusters on growing tips and stems. Pinch out affected tips and spray with soapy water, or encourage ladybirds.

Halo blight causes dark-edged spots on leaves and pods. Avoid overhead watering and remove affected material promptly.

Companion Planting

Runner beans grow well alongside sweetcorn and courgettes in a traditional three sisters planting arrangement. Avoid planting near onions and garlic, which can inhibit bean growth.