How to grow runner beans
Runner beans (Phaseolus coccineus) are among the easiest and most rewarding vegetables to grow. And with their colourful flowers and heart-shaped leaves, they look as good as they taste. Follow our simple guide for a bountiful harvest of runner beans.
Best runner beans to plant
Whether you’re planting runner beans in rows on your allotment or just growing a few plants in a pot, there are plenty of varieties to choose from. Here are some of the most popular types of runner beans:
- Runner bean ‘Red Rum’ AGM – a heavy cropper that does well in all weather conditions.
- Runner bean ‘Celebration’ AGM – very attractive, with pink flowers and tender, tasty pods, almost stringless when young.
- Runner bean ‘Tenderstar’ – pretty pink and red bicolour flowers and smooth, tender, stringless pods.
- Runner bean ‘Scarlet Emperor’ – bright red flowers and masses of smooth dark green pods that can reach up to 35cm (14in) in length.
- Runner bean ‘Snowstorm’ – white flowers and plenty of tasty pods.
- Runner bean ‘Hestia’ – a dwarf variety growing to 45cm (1.5ft) tall, ideal for containers.
To grow runner beans you will need:
- Bean seeds
- Small pots
- Multipurpose compost
- 2.4m long poles to create a support framework
- Garden fork and spade
- Garden compost or well-rotted farmyard manure
When and where to plant runner beans
Sow runner beans indoors in pots in mid-spring, or sow directly into the ground outdoors in late spring and early summer once all risk of frost is gone.
A rich, well-drained soil in full sun is ideal for planting runner beans. You can also grow them in containers filled with multipurpose compost.
Sowing runner beans indoors
- Fill small pots with multipurpose compost.
- With a dibber or pencil, make a hole 5cm (2in) deep in the compost and drop in a bean seed. Plant one seed per pot and sow a few extra pots in case seeds fail to germinate or young plants are eaten by slugs and snails.
- Cover over with compost and firm it down gently.
- Water the pots and put them on a sunny windowsill or in a greenhouse to germinate. This should take about one week.
- Let the seedlings grow on indoors until all risk of frost is past, then plant them out. Harden the seedlings off for a week before planting by placing the pots outside during the day and bringing them back in at night.
Sowing runner beans directly outdoors
- Dig the area over a few weeks before planting and clear the soil of all weeds and stones. Dig in well-rotted farmyard manure or compost to improve the soil structure and drainage.
- Rake the soil to create a level surface with a light, crumbly texture.
- Put in sturdy supports for the bean plants, such as two rows of poles sloping towards each other. Traditionally, the poles are tied together at the tops to create an A-frame but tying them in the middle to create an X-shape makes it easier to pick the beans, as they are not all clustered together at the top of the frame. Space the poles 45-60cm (1.5-2ft) apart. If you are only growing a few plants, a wigwam of poles makes a good support for them to climb up.
- Sow the bean seeds 5cm (2in) deep, sowing two seeds at the base of each pole.
- Water regularly.
- Once the seedlings are around 10cm (4in) tall, pull out the weaker seedling from each pair.
Tips on caring for runner beans
- Beans will twine automatically around their supports, but you may need to tie the young seedlings into the poles at first.
- Once the plants reach the tops of the supports, pinch out the growing tips. This will encourage the plants to put out side shoots, producing more beans.
- Water regularly, especially during dry periods and when the flowers are setting (i.e. developing into beans).
- Protect young plants from slugs and snails, using crushed eggshells, sawdust, beer traps, copper tape on pots, or wildlife-friendly pellets.
- Colonies of aphids often appear on young shoots. In large quantities they can distort the plant’s growth and reduce vigour. Check young plants and wipe off aphids as soon as you see them to stop them becoming a problem. Natural predators like ladybirds will help to control aphid infestations. If using pesticide sprays, always check that they are suitable for use on edible plants. To avoid harming pollinators, don’t spray when the plants are in flower.
- In hot, dry weather, flowers sometimes drop off the plant without developing into beans. Regular watering will help, and the problem usually resolves itself once cooler weather returns.
Growing runner beans in containers
If you’re short on space, dwarf runner beans are ideal for containers, growing into bushy plants around 45cm (1.5ft) tall.
- Choose a container at least 30cm (1ft) in diameter, with good drainage holes. Fill with multipurpose compost.
- Sow seeds 5cm (2in) deep directly into the compost in late spring or start seedlings indoors in mid-spring and transplant into the container once they are big enough (around 10cm/4in tall).
- Water regularly and feed the plants with a high potassium feed (such as tomato feed) fortnightly once the flowers start setting.
Harvesting runner beans
Harvest runner beans when the pods are between 15-20cm (6-8in) long, before the beans start to swell in the pods. Harvesting runner beans encourages the plant to produce more, so pick frequently.
Common problems and pests of runner beans
Pods failing to set
One of the most common runner beans problems is plants flowering but failing to develop pods. This can be caused by a range of environmental conditions, including very hot weather, lack of water, few pollinators, and birds damaging flowers. The problem often resolves itself as the season progresses.
- Water plants regularly in dry periods.
- Plant near other flowering plants to attract more pollinators.
Blackfly is a small black sap-sucking insect that infests the soft new shoots on bean plants, stunting and distorting them. The best way to get rid of blackfly on runner beans is to check regularly and tackle the problem as soon as it appears.
- Wipe off small colonies with a damp cloth.
- Encourage natural predators like ladybirds and hoverflies.
- Pesticide sprays are available for blackfly.
Slugs and snails
Slugs and snails will eat the leaves of young runner bean seedlings, and can be identified by the slime trails that they leave, as well as the damage they do. As the plants grow taller, they are less at risk of slug and snail damage.
- Check plants at night and remove slugs and snails by hand.
- Covering the soil around plants with crushed eggshells or grit may have some effect.
- Scatter environmentally-friendly slug pellets if other methods are insufficient.
Key features of runner beans
|Flowering season(s)||Summer, Autumn|
|Foliage season(s)||Spring, Summer, Autumn|
|Soil type||Chalky, Clay, Loamy, Sandy|
|Soil moisture||Moist but well-drained|
|Ultimate height||Up to 1.8m (6ft)|
|Ultimate spread||Up to 30cm (1ft)|
|Time to ultimate height||6 months|