How to grow Runner Bean (Scarlet Emperor)

Phaseolus coccineus

🥕 Vegetable 🌱 Grown each year

Tall climbers with scarlet flowers and long, flavourful pods — a classic of British allotments.

At a glance: Sow late April to late May, harvest from mid July.

When to sow, plant and harvest

JanFebMarAprMayJunJulAugSepOctNovDec

Sow outdoors

Flowers

Harvest

Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.

Late April – late May · 2 weeks after the last spring frost
Sow Seeds Outdoors
Sow thinly in drills where they are to grow.
7–14 days after “Sow Seeds Indoors” · Early May – mid May
Check Germination
Seedlings should appear in 7–14 days. If sown outdoors, thin to 20 cm up canes apart when big enough to handle.
7–21 days after “Plant Out” · Mid May – late May
Add Support
Tie young plants to a wigwam or double row of 2.4 m canes; they twine anticlockwise.
30–45 days after “Add Support” · Mid June – late June
Pinch Out at Cane Tops
When stems reach the top of the canes, pinch them out to encourage side shoots lower down.
7–14 days after “Pinch Out at Cane Tops” · Mid June – late June
Water Well in Flower
Water generously when flowering — dry roots make flowers drop without setting pods.
71–92 days after “Check Germination” · Mid July – early August
Start Harvesting
Pick every few days while pods are 15–20 cm and snap cleanly; old pods stop new ones forming.
70–100 days after “Start Harvesting” · Late September – late October
Finish and Clear
Cut stems at ground level and leave the nitrogen-rich roots in the soil.