French Bean
Phaseolus vulgaris
French beans (also called green beans or string beans) are a warm-season staple that produce slim, tender pods with a finer flavour and texture than runner beans. Dwarf (bush) varieties grow 45cm tall and need no support, making them ideal for smaller plots and containers, while climbing types reach 2m and produce heavier yields over a longer season. Sow directly outdoors from mid-May once the soil has warmed to at least 12°C, or start in pots indoors from late April. They're less fussy than runner beans — they don't need the rich, moisture-retentive trench, though they appreciate fertile, well-drained soil. Unlike runners, French beans are self-pollinating, so flower drop in hot weather is rarely an issue. Harvest dwarf varieties from July, climbers from August. Pick pods when young and pencil-thin (10–15cm) for the best flavour and to encourage continuous production. Popular dwarf varieties include 'The Prince' and 'Safari'; for climbers, 'Cobra' and 'Blue Lake' are excellent. Purple-podded varieties like 'Purple Teepee' are easy to spot among the foliage, though they turn green when cooked. Surplus beans freeze well — blanch for 2 minutes, cool, and freeze flat on trays.
Plan where to grow French Bean using our vegetable garden planner.
When to Sow French Bean
Sow french bean in April, May, June, July.
Time to Harvest French Bean
Expect to harvest approximately 2 months after sowing, usually from July to September.
Companion Plants for French Bean
- Nantes Carrot
Dwarf French beans and carrots are traditional neighbours; the beans fix nitrogen and cast little shade.
- Butterhead Lettuce
Lettuce fills the gaps between dwarf bean rows and appreciates their light shade in midsummer.
- Radish
Radishes can be sown between bean rows and pulled before the beans spread.
- Lamb's Lettuce
Lamb's lettuce can be sown into the ground as beans finish in late summer.
Avoid growing french bean near
- Garlic: Alliums are traditionally kept away from peas and beans, which are said to grow less well beside them.
- Onions: Onions are traditionally kept away from peas and beans, which are said to grow less well beside them.
- Fennel: Herb fennel is widely reported to inhibit the growth of many crops nearby, so it is best kept in its own spot.
Expected Yield
Dwarf varieties crop for 4–6 weeks; climbers for 8–10 weeks. Expect 3–4kg per 3m row.
Growing Tips
Self-pollinating; more reliable pod set than runner beans
Common Problems with French Bean
Poor germination in cold soil
French beans need soil temperatures of at least 12°C to germinate reliably. Sowing too early in cold, wet soil leads to rotting seeds. Warm the soil with cloches or black polythene for 2 weeks before sowing. Alternatively, start seeds in pots on a warm windowsill and transplant after the last frost.
Slugs eating seedlings
Emerging seedlings are extremely vulnerable to slug damage in the first 2–3 weeks. Start plants in pots and transplant when 10cm tall for better survival rates. If direct sowing, use organic slug pellets, copper barriers, or nematode biological control. Once plants are established, slug damage is minimal.
Bean seed fly
Larvae burrow into germinating seeds, hollowing them out so they fail to emerge. Most common in cool, wet springs and freshly manured soil. Sow in warmer conditions, start in pots to avoid the problem entirely, or cover direct sowings with fleece. Avoid incorporating fresh manure just before sowing.
French Bean: common questions
When should I sow french bean in the UK?
Sow french bean from April to July. Sow under cover for an early start, or directly outside once the soil has warmed.
How far apart should I plant french bean?
Space french bean about 15cm apart. It grows to around 45cm tall. Sow seeds 5cm deep.
How long does french bean take to germinate?
French Bean seeds usually germinate in 7–14 days at 12°C+, depending on temperature.
When is french bean ready to harvest?
In the UK, french bean is usually harvested from July to September. It's ready about 2 months after sowing.
Does french bean come back every year?
No. French Bean is an annual: it grows, flowers and dies in one year, so sow it again each year. Some annuals self-seed if a few flowers are left to set seed.
What grows well with french bean?
Good companions for french bean include Nantes Carrot, Butterhead Lettuce, Radish and Lamb's Lettuce. See the companion plants section above for why each one helps.
What should I not plant near french bean?
Avoid garlic: alliums are traditionally kept away from peas and beans, which are said to grow less well beside them. Avoid onions: onions are traditionally kept away from peas and beans, which are said to grow less well beside them. Avoid fennel: herb fennel is widely reported to inhibit the growth of many crops nearby, so it is best kept in its own spot.
Is french bean frost hardy?
No. French Bean is tender and is damaged by frost, so keep it under cover until all risk of frost has passed and bring it in, or grow it under glass, when nights turn cold.
What crop rotation group is french bean in?
French Bean belongs in the legumes group for crop rotation. Grow it in a different bed each year, alongside other legumes, so pests and diseases don't build up in the soil.
French Bean guides
Plan your french bean in the allotment planner
Drag and drop plants onto your plot and get personalised sowing reminders.
Open PlannerMore Vegetables
Garden Pea
Pisum sativum
There are few greater pleasures in the allotment than eating fresh peas straight from the pod — the sugars start converting to starch the moment they're…
Mangetout
Pisum sativum var. saccharatum
Mangetout (literally 'eat all') are flat-podded peas harvested young, before the seeds swell. They're picked at a stage when garden peas would still be…
Garlic
Allium sativum
Garlic is one of the easiest allotment crops to grow, needing minimal attention between planting and harvest. Autumn planting (October–November) is preferred…
Globe Artichoke
Cynara cardunculus var. scolymus
Globe artichokes are as much an architectural garden feature as they are a crop — their dramatic silvery-grey foliage and enormous thistle-like flower heads…