How to Plant Runner Beans

Runner beans are easy to grow and highly productive, making them a favourite for UK gardens. Planting them involves preparing the soil well, choosing the right location, and giving them the support they need to climb. Whether you're starting them indoors or sowing directly outside, a bit of planning at the beginning of the season pays off later when you're picking beans by the handful.

What Are Runner Beans?

Runner beans are vigorous climbing plants that produce long, tender pods filled with edible seeds. Originally from Central America, they’ve been a UK garden staple for centuries. Not only do they offer a steady supply of beans, but they also add colour to your garden with their bright red or white flowers.

How to Sow Runner Beans Indoors

Sow runner beans indoors from mid-April using deep pots or root trainers filled with seed compost. Push each seed in about 5cm deep and keep them in a warm place—ideally around 15°C or warmer. Keep the compost moist, not soaked. Once the seedlings are about 10–15cm tall and have developed a few leaves, harden them off by placing them outdoors during the day before planting out after the last frost.

How to Direct Sow Runner Beans Outdoors

Sow runner beans directly into the ground from mid-May once all danger of frost has passed. Pick a sunny, sheltered site with fertile, well-drained soil. Sow seeds 5cm deep and around 20–25cm apart. Water well and keep the soil moist until they germinate, which usually takes about a week to ten days in warm weather.

How to Support Runner Beans

Runner beans need tall support structures. Use canes or bamboo poles tied together in a wigwam or A-frame shape. The supports should be at least 2 metres tall. Plant one or two seeds at the base of each cane. As the plants grow, help them find the canes and twine around them—after that, they’ll climb on their own.

How to Feed and Care for Runner Beans

Runner beans are heavy feeders. Before planting, enrich the soil with well-rotted manure or compost. During the growing season, apply a liquid fertiliser every couple of weeks, especially once flowers appear. Water regularly, particularly in dry spells, and keep the base of the plants weed-free.

When to Harvest Runner Beans

Runner beans are usually ready to harvest 12 to 16 weeks after sowing. Pick them when they’re young and tender, about 15–20cm long. Leaving them too long results in tough, stringy pods. Harvesting regularly also encourages the plant to keep producing new pods.

Why Do My Runner Beans Fail to Set Pods?

Lack of pod set is often down to poor pollination, which can happen in cold or windy weather when pollinators are scarce. Dry soil and too much nitrogen can also lead to lush growth with few flowers or pods. Keep the soil evenly moist and try gently misting the flowers with water to encourage setting.

When to Pick Runner Beans?

Pick runner beans when the pods are firm but still snap easily when bent. Once the beans inside start bulging, the pod becomes stringy and less pleasant to eat. Frequent picking—every couple of days in peak season—keeps the plant producing more.

How to Pick Runner Beans?

Hold the vine with one hand and gently snap or snip the pod off with the other to avoid damaging the plant. Use scissors or secateurs if the stem is tough. Don’t tug, as that can break the vine or loosen its grip on the support.

How Long Do Runner Beans Take to Grow?

Runner beans typically take between 12 and 16 weeks from sowing to harvest, depending on weather conditions. You’ll see germination within a week or two, and the plants will climb rapidly once established.

Which Way Up to Plant Runner Beans?

Plant seeds with the eye (a small mark or scar) facing downwards. While they’ll usually grow no matter the orientation, this encourages faster, more consistent germination and root development.

Will Runner Beans Recover from Frost?

Runner beans are not frost-hardy. Even a light frost can damage or kill young plants. If a late frost is forecast, cover young seedlings with cloches or fleece. Damaged plants won’t usually recover well, so protect them or wait to plant until the risk has passed.

What Spacing Do I Need for Runner Bean Plants?

Space seeds or plants about 20–25cm apart, with 45–60cm between rows if growing in double rows or beds. Good spacing ensures airflow, helps prevent disease, and gives each plant room to climb and produce pods.

Pests, Diseases and Common Issues

Aphids, blackfly and slugs are common problems. Use organic sprays or encourage predators like ladybirds to keep them under control. Bean rust and halo blight can affect leaves and pods, especially in wet summers. Rotate crops each year and avoid overhead watering to help reduce fungal issues.

How to Make a Runner Bean Frame?

Create a wigwam by tying 6–8 tall canes together at the top and spreading them evenly in a circle at the base. For rows, lean canes in from each side and tie them to a horizontal bar at the top to form an A-frame. Secure well so it can handle the weight of mature plants.

Which Way Do Runner Beans Twine?

Runner beans naturally twine in a clockwise direction (when viewed from above). When training them up canes, wind them the same way to help them grip and climb more quickly.

How Tall Do Runner Beans Grow?

Runner beans can grow to over 3 metres tall in good conditions. Providing tall, stable supports and regular feeding ensures they reach their full height and produce plenty of pods.

Pre-Soaking Seeds Can Help

Runner bean seeds have a tough outer coating. Soaking them in water for a few hours before sowing (no more than overnight) can help speed up germination, especially in cooler soil. That said, don’t overdo it—soaked seeds can rot if planted in soggy conditions.

Wind Protection Matters

Runner beans grow tall and can act like sails in the wind. In exposed sites, strong gusts can snap stems or topple supports. Consider planting near a wall, fence, or hedge that offers shelter, or install windbreak netting if needed.

Companion Planting Can Be Useful

Runner beans do well near sweetcorn, nasturtiums and lettuce. Avoid planting them near onions or garlic, which can inhibit growth. Companion planting can also help deter pests and attract pollinators.

Keep Picking to Prevent Coarseness

The more often you pick, the more the plant produces. Leaving pods on the plant signals it to stop flowering. Once the seeds inside start swelling, pods become fibrous and tough. Don’t let them get past their prime unless you're saving seeds.

Save Seeds from the Best Plants

If you want to save seeds for next year, let a few pods mature fully on the healthiest, most productive plants. Allow them to dry on the vine, then store seeds in a cool, dry place. Just keep in mind that hybrid varieties won’t grow true from saved seed.

Dig a Trench in Winter

For a traditional and effective growing method, dig a trench in winter where you plan to plant your beans. Fill it with compostable kitchen waste (veg peelings, shredded paper), then cover it with soil. By spring, it’ll have broken down into rich material that holds moisture—a big plus during dry spells.