Last autumn (October 2024), I tried four different green manures: forage rye, bird's foot trefoil, forage pea and field beans. Forage rye and field beans were, by far, the most successful as green manures. It is the latter that I will be discussing in this post. As a member of the legume family, fleid beans are able to fix nitrogen in the soil as well as providing organic matter (dug in or composted) and ground cover to suppress weeds (see Photo 5).
After clearing the French bean plot, several rows of field beans were sown (up to the white post) on the 7th October into 'dibbed' holes (Photo 1).
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Photo 1: Five Long Rows of Field Beans Sown (7th October 2024) |
As soon as the courgettes had finished (see
Photo 1), a further three rows were sown. Germination rates were excellent (
Photo 2) ...
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Photo 2: Eight Rows of Field Beans (1st November 2025) |
At the top of the plot (
Photo 2 &
Photo 3) are forage peas which didn't grow on despite a
mild December.
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Photo 3: Forage Peas & Forage Beans (1st January 2025) |
Growth over the January-March period was slow but steady (
Photo 4) ...
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Photo 4: Field Beans (3rd April 2025) |
... but really took off in April ...
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Photo 5: Field Beans (18th April 2025) |
The bottom half of the plot was cleared for the onion sets, which were
planted a month earlier, and are coming along nicely.
I now had two options: (i) cut down and dig in as a green manure, or (ii) allow the plants to grow on to maturity and produce an edible crop after which the stalks and leaves would be composted.
I decided on the latter course of action because, although we always have a problems with
blackfly, we do enjoy broad beans (
aka fava or faba beans). Generally speaking, overwintered broad beans are less prone to blackfly infestation and that was certainly the case with these autumn-sown field beans. Considering there were over a hundred plants in this plot, I only had to cut out the tips of about five plants with minor infestations.
And grow they certainly did. Reaching 3-4 foot high (1 - 1.2 metres) by mid-May (Photo 6) ...
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Photo 6: Metre-high Field Beans (12th May 2025) |
... and 5-6 feet tall (1.5 - 1.8 metres) in early June when they were ready for harvesting (
Photo 7).
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Photo 7: Fully-grown Field Beans (10th June 2025) |
Field beans produce small pods (2-4 inches, 5-10 centimetres) containing 3-5 centimetre-long beans (
Photo 8). Modern broad bean cultivars produce longer pods (15-25 centimetres) with 5-8 larger beans/pod.
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Photo 8: Field Bean Pod (10th June 2025) |
The beans can be eaten raw or cooked (steamed/boiled/fried) or frozen/dried for longer-term storage. The first pod pickings (230 g, Photo 9) yielded 66 grams of beans which were added to a curry in the slow cooker. Delicious!!
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Photo 9: First Field Bean Pickings (10th June 2025) |
And also
nutritious! A 100 g portion contains 26 g of protein and 25 g fibre and is a good source of B vitamins and trace elements (especially copper, iron, magnesium, manganese, phosphorus, potassium, selenium and zinc).
It has been
suggested that broad bean flour would be a nutritious and sustainable addition to bread flour in the United Kingdom or other places where broad beans are grown. You can also
save the beans for sowing in the next growing season.