From a Worcester Allotment: Discover Flageolet beans

Flageot blanc

The Flageolet bean is a type of bean of the species Phaseolus vulgaris which was originally developed in France in the 1800s under the varietal name of "Nain hâtif de Laon" , meaning 'Laon Early Dwarf'.
Flageolet beans are small immature kidney beans, and many dwarf cultivars belonging to this variety are known and were formally known in France under the trade name of "flageolets".
The light green Flageolet bean is revered in France and soon the heirloom Chevrier variety will come under a controlled label reminiscent of the wine "Appellation d'Origine Controllée" called "Label Rouge". A number of other beans are already produced under this label.
Many claim that it has a delicate flavour found in no other Phaseolus but perhaps reminiscent of green soya bean (Asian opinion) or Lima bean (American opinion), no doubt this is influenced by the "cute look" of the seeds reinforced by the prestige attached to the exclusive origin of this vegetable - if it pleases the Parisien gourmets' palate it has to be par excellence.

Know your Flageolet bean - Botany

The flageolot bean is an annual.
The maximum bush height is 25 to 38 cm (10 to 15 inches).
The spread of each bush is 10 to 20 cm, occasionally to 30 cm (4 to 8 inches, and 12 " on occasions).
Most of the root system is confined between 2 and 5 cm, some of the roots reaching 1m deep in ideal conditions (5 to 7.5 inches, down to 25").
Propagation is by seeds only.
Seed longevity is 3 years to 5 years in good dry and cool conditions.
The harvest/sowing ratio is 25 to 40 (ie. 2 kg of seeds sown, 50 to 80 kg of seeds harvested).

Its most remarkable feature is its seed, smaller than other kidney-bean seeds, and of an attractive pale green colour, a fairly rare trait within the Phaseolus vulgaris species.
However, if you treat the flageolet as any other bean in the field, then all you will have is a very ordinary-looking white-seeded, low-yielding bean.
The "magic touch" of the growers has to do with the picking and the drying process.
The seed is at its very peak for colour and flavour in its fresh or semi-dry state (something that can hardly be expected from tinned seeds). It then needs very little cooking and just melts in the mouth.
To obtain semi-dried seeds the whole plant can be pulled up and hanged upside down in a shed to dry ( this will limit infection by diseases such as Anthracnose which could spoil a number of seeds on non resistant varieties ), and the pods picked when a dull green and feeling dry to the touch.
If the plants are left in the ground the pod colour may be closer to gray rather than green and the harvest period for this specific purpose slightly reduced.
Any seed past the semi-dry stage can be consumed dried so nothing is lost... except the colour and freshness.
Moreover in good growing conditions seeds can be produced and stored for sowing in ensuing years.

In order to obtain fresh seeds the pods have to be harvested when well filled but still green.
Only a few varieties of Phaseolus can be easily shelled at that point.
They fall into the generic name of "horticultural beans" or "shelling beans" in America, are known as green-shell-beans.
The Italian Borlotti (light & dark brown seed) and Cannellini (white seed) are probably the best known of this type around the world.
The flageolet can also be consumed at the "green bean" stage, like some other "horticultural beans" although this is of short duration because the pod is not stringless.
In case of an excessive production the shelled fresh seeds can be frozen like peas, preferably after a short period of blanching.
The unshelled beans can also be frozen if time is short and all pods cannot be shelled at once.

In traditional French cooking the flageolet is most famous as an accompaniment to a roasted leg of lamb but it certainly is not its only possible use.
It does not require presoaking or precooking and would be easily digested by most people because at that stage it has not developed many of the anti enzymes normally making beans difficult to digest.
The seeds skin being thinner than in other Phaseolus vulgaris cultivars also facilitates digestion.

Know your Flageolet bean - Varieties

The bean is available in a variety of colours including white (flageolet blanc), black (noir), yellow (jaune), red (rouge) or green (vert).
Flageolet bean varieties include: