When Is the Right Time to Harvest Beans?

Beans are fast. From ideal eating size to over-mature and stringy can be a matter of four or five days, especially during a warm spell. Regular picking is essential — every bean you leave on the plant triggers the plant to slow production, so missing the window costs you twice: you get inferior beans and fewer of them.

French and Dwarf Beans

French beans (also called climbing or dwarf green beans) are best harvested young, when the pod is slim — about pencil thickness — and snaps cleanly when bent. At this stage there is barely any seed visible inside the pod. If you can feel pronounced bumps along the pod, the seeds are swelling and the beans are turning starchy. They are still edible but will need longer cooking and will not have the sweet, tender quality of a young bean. Check plants every two days in warm weather. A single plant in full production can set eight to twelve pods in a week.

Runner Beans

Runner beans develop more quickly than French beans and can become tough and stringy within days. The ideal size is 15–20 cm: pods should feel flat and flexible, without bulging seeds. If you see the bean seeds pressing clearly against the pod skin, the strings will be tough and the flavour starchy. Pick at least every three days; in hot weather, every two. Never let pods dry and yellow on the plant — this signals the plant to stop flowering. If you go on holiday and return to a crop of over-mature runners, strip the plants completely, compost the tough pods, water well, and the plant will reflower within two weeks.

Broad Beans

Broad beans are the only type where you can choose your harvest moment based on what you want to cook. Very young pods — under 8 cm — can be eaten whole, pod and all, like mangetout. Once pods reach 10–15 cm, shell them and eat the beans inside fresh and green. Left to grow further, the beans inside develop a white, floury texture suited to drying and storing. For eating fresh, pick when the beans inside feel firm but not hard and the skin around each individual bean is tender. The black scar on the inner curve of a broad bean turns black as it ages — pale-scarred beans are younger, sweeter, and more tender.

Borlotti and Drying Beans

Borlotti and other shelling beans are left on the plant until the pods begin to turn yellow and papery. Harvest before the first frost. Shell immediately, spread on a tray, and dry in a warm airy spot for two to three weeks until the beans rattle inside, then store in jars. Do not rush the drying — any residual moisture causes mould in storage.