Legume
How to grow runner beans
Phaseolus coccineus
Sow runner beans indoors in late April or outdoors from mid May, and plant out after the last frost against 2.4 m canes in soil enriched with plenty of compost. They are thirsty rather than hungry: steady water at the roots from first flower is what sets pods. Pinch out the tops when they reach the top of the canes and pick every two or three days to keep them cropping until the first frost.
- Hardiness
- Tender
- Position
- Full sun, sheltered
- Soil
- Deep, rich, moisture-retentive
- Ideal pH
- 6.5 to 7.0
- Water
- High, the biggest factor in flowers setting pods
- Feeding
- Moderate feeder
Sowing and planting runner beans
WhenSow May indoors or late May to Jun direct; harvest Jul to Oct
Starting off
Sow indoors late April to May, one seed 5 cm deep in a 9 cm pot or root-trainer at 15 to 20 °C, germinating in 7 to 14 days; plant out late May to early June after frost. Direct sow mid May to June into soil above 12 °C, two seeds per cane. A second sowing in late June keeps picking into October. Pinch the tip at the cane top.
Spacing and planting
Plant 15 cm apart in a double row 60 cm apart up 2.4 m canes crossed and tied at the top, or 8 plants around a wigwam of canes 30 cm apart. Sow 5 cm deep. A wigwam of 5 to 6 plants crops in a 45 cm pot or half-barrel with daily watering; dwarf 'Hestia' manages a 30 cm pot.
Varieties worth growing
- Scarlet Emperor
- The classic red-flowered bean: long, heavy cropping, best flavour, but sets poorly in a heatwave.
- White Lady
- White flowers that bees pollinate and birds leave alone; sets in hot weather when the reds drop.
- Firestorm
- Red-flowered and self-fertile, so pods set without pollinators and in a dry summer. Stringless.
- Moonlight
- White, self-fertile, stringless and early; the one for a difficult site.
- Hestia
- Dwarf bush to 45 cm for a 30 cm pot or the front of a bed; red and white flowers.
Runner beans month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Order seed. Dig the bean trench and fill it with kitchen waste and compost through the winter.
- February
Keep filling the trench. Buy canes.
- March
Cover the trench with soil. Put up canes on a still day.
- April
Sow indoors at the end of the month, one seed 5 cm deep per root-trainer or 9 cm pot.
- May
Sow a second batch. Harden off. Direct sow after mid May once soil is above 12 °C.
- June
Plant out in the first week. Tie in loosely until they twine. Second sowing late June for October picking.
- July
Pinch out tips at the cane top. Water heavily in the evening. High-potash feed fortnightly from first flowers.
- August
Pick every two or three days. Never let a pod mature or the plant stops.
- September
Keep picking. Let a few pods on the best plant mature for next year's seed.
- October
Last picking before frost. Cut plants at the base, leave the roots in the soil.
- November
Take canes down, clean and store them dry.
- December
Rest.
Feeding runner beans
A legume: it fixes its own nitrogen. Organic matter for moisture, potash for pod set, and no nitrogen at all.
Fixes its own nitrogen, so go easy on N. Instead enrich the soil with organic matter for moisture, and use potassium to support flowering and pod set.
Feeding plan
Winter, the bean trench
Compost and kitchen waste
A spade's depth of trench, 60 cm wide, filled over winter and covered in March.
Planting
100 to 200 g/m² forked into the top of the trench, which is 60 to 120 g per metre of a 60 cm wide double row; no nitrogen.
First flowers, then every 2 weeks
3 to 6 ml per litre as a drench; in pots at every second watering.
Flowering, dry summers
20 to 50 g/m² scattered and watered in, once: 12 to 30 g per metre of a 60 cm wide double row.
Signs to watch
Flowers dropping without setting pods in July
Dry roots, warm nights over 16 °C or no pollinators, not nutrition
Mulch, water heavily and grow white-flowered 'White Lady' or self-fertile 'Firestorm'
Pale, yellowish early leaves
Root nodules not yet active in cold soil
Wait
All leaf and few flowers
Excess nitrogen from fresh manure
High-potash feeding
Pests, diseases and problems
Seedlings eaten off at soil level, leaves shredded
Slugs and snails
Start plants in pots and plant out at 15 cm, protect with a cloche for the first week, torch patrols.
Black insects crusted along stems and under leaves from June
Black bean aphid (blackfly)
Pinch out the growing tip once the plant reaches the cane top, spray soft soap, and leave hoverflies to it.
Direct-sown seed rots or seedlings come up with no leaves
Bean seed fly, or cold wet soil
Sow in pots under cover and plant out, or sow direct only once the soil is above 12 °C.
Flowers drop and no pods form in July
Dry roots, nights above 16 °C, or no bees
Mulch and water heavily in the evening, grow a white or self-fertile variety, plant something flowering for the bees.
Water-soaked spots with a yellow halo on leaves, pods spotted
Halo blight, seed-borne
Buy fresh seed, do not save seed from affected plants, remove worst plants.
Flowers nipped off and dropped
Sparrows
Try a white-flowered type, which often draws them less, or net until pods set.
Harvest and rotation
Harvest and storage
Pick pods at 15 to 20 cm when they snap cleanly, before the beans swell and the pod turns stringy, 12 to 14 weeks from sowing; pick every 2 to 3 days with a twist, because one pod left to mature stops the plant. A 3 m double row gives 20 to 30 kg from July to October. Keep 3 days in the fridge; slice and freeze.
Rotation and companions
Rotation: legume group with peas and beans, 3-year gap; brassicas follow them to use the fixed nitrogen, and the roots are left in the soil at the end of the year. Keep away from onions and garlic, which check bean growth, and from fennel.
Good to knowDig a moisture-holding trench; consistent water is the single biggest factor in flowers actually setting pods. Pick often.
Growing runner beans in pots
A wigwam of five or six plants crops well in a 45 cm pot or a half-barrel of at least 40 litres; Hestia manages a 30 cm pot. Use a water-retentive mix (multipurpose plus a third loam-based compost) and the PK Fertiliser through it. Nothing in a pot drinks like a runner bean in August: water every evening until it runs out of the base, and twice on hot days. Set the canes before you plant and tie the top firmly, because a loaded wigwam catches the wind.
Runner beans: common questions
Why are my runner beans flowering but not setting pods?
Dry roots, warm nights and a shortage of bees, in that order. Soak the row every evening in dry weather and mulch. Red-flowered varieties set badly above 16 °C at night; white or self-fertile ones such as Firestorm and Moonlight carry on.
Do runner beans need feeding?
Not with nitrogen: they fix their own. Give them a trench of organic matter for moisture, a zero-nitrogen PK feed at planting, and a high-potash liquid feed fortnightly from the first flowers.
Should I leave bean roots in the ground?
Yes. Cut the plants off at soil level in October and leave the roots. The nitrogen nodules break down over winter and feed the brassicas you plant there next.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.