Legume
How to grow French beans
Phaseolus vulgaris
French beans are tender, so everything depends on warmth. Sow indoors in late April, or direct from mid May to mid July once the soil is above 12 °C, in full sun and free-draining soil. Dwarf varieties crop within 10 weeks and need no support; climbers need 2 m canes and crop for longer. Protect young plants from slugs, water well once the flowers open and pick every two or three days to keep the pods coming.
- Hardiness
- Tender, sow only into warm soil
- Position
- Full sun, warm
- Soil
- Fertile, free-draining, warm
- Ideal pH
- 6.0 to 7.0
- Water
- Moderate, most at flowering and pod fill
- Feeding
- Light feeder
Sowing and planting French beans
WhenSow May to Jul in succession (indoors from late Apr); harvest Jul to Oct
Starting off
Sow indoors from late April, one seed 4 to 5 cm deep in a 9 cm pot or root-trainer at 15 to 20 °C, germinating in 7 to 14 days, and plant out late May to June after frost. Direct sow mid May to July into soil above 12 °C; seed rots in cold, wet ground. Sow dwarf types every 3 weeks until mid July.
Spacing and planting
Dwarf types 15 cm apart in rows 45 cm apart, or 20 cm each way in a block; climbers 15 cm apart in double rows 60 cm apart up 1.8 to 2.4 m canes. Sow 4 to 5 cm deep. Dwarf beans crop well in a 30 cm pot at 5 plants per pot; climbers suit a wigwam in a 45 cm tub.
Varieties worth growing
- Safari
- Dwarf Kenyan type with slim, stringless pencil pods held above the leaves. Good disease resistance and the fine beans you see in shops.
- Purple Teepee
- Dwarf with deep purple pods carried clear of the foliage, so they are easy to see and pick. Pods turn green when cooked.
- The Prince
- Old dwarf variety with long, flat pods, early and heavy, best picked young.
- Cobra
- The most reliable climber: long, round, stringless pods from July to the frosts, and it also crops well in a greenhouse or polytunnel.
- Borlotto Lingua di Fuoco
- Climbing borlotti bean with red-splashed pods, grown for the fat speckled beans inside, eaten fresh in September or dried for winter.
French beans month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Nothing to do.
- February
Nothing to do. Order seed.
- March
Nothing to do. It is too cold, however mild the week.
- April
Sow in pots indoors in the last week. Cover the bed with cloches or black plastic to warm it.
- May
Sow direct from mid month under cloches. Harden off and plant out indoor sowings at the end of the month.
- June
Plant out and sow direct. Put up canes for climbers and guide the first shoots onto them.
- July
Last sowing of dwarf varieties by mid month. First pickings. Water well at flowering.
- August
Pick every two or three days. Mulch after rain.
- September
Keep picking. Cover late dwarf sowings with cloches. Leave borlotti pods to dry on the plant.
- October
Pick the last pods before the first frost. Bring drying pods indoors to finish. Cut plants off at ground level.
- November
Nothing to do.
- December
Nothing to do.
Feeding French beans
A light feeder that fixes its own nitrogen once the soil is warm. Garden soil in reasonable condition needs nothing added; plants in pots need a liquid feed once the pods start.
Nitrogen-fixing, so little or no N needed; a little potassium aids cropping. Don't sow into cold soil.
Feeding plan
Winter or spring before sowing
Garden compost
A 3 to 5 cm layer forked in or left as a mulch. It holds the moisture that French beans need at flowering.
Sowing or planting, poor or new beds only
100 g/m², the label maintenance rate: about 45 g per metre of row for dwarf beans in rows 45 cm apart (100 x 0.45). On fertile soil, none.
Once the first pods form, pots only
3 to 4 ml per litre of water once a week: 30 to 40 ml in a 10 litre can. Do not exceed 4 ml per litre.
Flowering to pod fill, open ground on light soil
1 g per litre of water as a drench or foliar spray every 2 to 3 weeks. Optional; water matters more.
Signs to watch
Yellow, pale seedlings in May
Cold, wet soil stalling root nodules, not a nitrogen shortage
Fleece and wait for warmth
Older leaves yellow between the veins on light soils
Magnesium short
Epsom salts spray
Flowers dropping and curled, pitted pods
Dry roots at flowering
Mulch and water 10 litres per square metre twice weekly
Pests, diseases and problems
Seedlings eaten to a stump in the first fortnight after emerging or planting out
Slugs and snails, the main cause of failure with French beans
Raise plants in pots and set them out at 8 to 10 cm tall with two true leaves, water in the morning, check at night with a torch, and use nematodes on warm, moist soil.
Seed fails to come up, or seedlings emerge ragged with the growing point missing
Bean seed fly maggots, or seed rotting in cold, wet soil
Do not sow outdoors before mid May, avoid ground with freshly dug-in manure or green material, and start early sowings in pots indoors.
Black aphids clustered on shoot tips and under leaves in June and July
Black bean aphid
Squash colonies or wash them off with a jet of water before they spread to the pods; pinch out badly infested tips on climbers that have reached the top of their canes.
Small brown spots ringed with a yellow halo on the leaves; greasy spots on pods
Halo blight, a bacterial disease carried in the seed and spread by rain splash
Pull up and bin affected plants, do not handle the crop when wet or save seed from it, and buy fresh seed from a good supplier.
Leaves pale and finely speckled, drying up in hot weather or under glass
Red spider mite
Water thoroughly and mist the foliage in the evening; under cover damp down daily and introduce the predator Phytoseiulus persimilis.
Harvest and rotation
Harvest and storage
Pick pods at 10 to 15 cm when they snap cleanly, 10 to 12 weeks from sowing; hold the stem and pull with a twist, picking every 2 to 3 days to keep the plant flowering. A dwarf plant gives 250 to 500 g, a climber 1 to 1.5 kg. Keep 3 days in the fridge or blanch and freeze; leave late pods to dry on the plant for haricots.
Rotation and companions
Rotation: legume group, 3-year gap, followed by brassicas or leafy crops that use the fixed nitrogen; leave the roots in the ground. Dwarf beans fit between rows of sweetcorn, brassicas and celery, fixing nitrogen without shading. Keep away from onions, garlic and leeks, which inhibit bean growth.
Good to knowDwarf types need no support; pick young and regularly for tender beans.
Growing French beans in pots
Dwarf French beans are among the most productive vegetables for pots. Grow five plants in a 30 cm pot (about 15 litres) of peat-free multipurpose compost, or build a wigwam of four 1.8 m canes in a 45 cm tub for climbers, one plant to each cane. Do not add fertiliser to fresh compost. Stand the pot in full sun out of the wind, water daily once flowering starts, and begin the weekly liquid feed when the first pods appear. A pot sown in early July and moved into a greenhouse in September crops into October.
French beans: common questions
What is the difference between French beans and runner beans?
French beans have smaller, smoother, more tender pods and are self-pollinating, so they set a crop in hot, dry spells when runner bean flowers drop. They come as dwarf bushes as well as climbers and are quicker to crop, but they are less tolerant of cold and need warmer soil to start.
Do French beans need support?
Dwarf varieties do not, though a few twigs stop plants heavy with pods from flopping onto wet soil. Climbing varieties need 1.8 to 2.4 m canes or netting, set up before planting, and twine up by themselves after a little help at the start.
Why are my French beans not producing pods?
Dry roots at flowering are the usual reason, followed by cold nights early in the season and too much nitrogen. Water thoroughly twice a week once the flowers open, mulch, and avoid nitrogen feeds. Leaving old pods on the plant also stops new ones forming, so pick often.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.