How to grow Flageolet bean

Phaseolus vulgaris L. (Flageolet Group) 'Flagrano'

How to grow Flageolet bean - Introduction

• • The Flageolet bean, Phaseolus vulgaris L. (Flageolet Group), Green seeded Flageolet, Green Flageolet is known in France as Haricot Flageolet à grain vert, and is a French bean of the haricot type.

• The caviar of beans; flageolets are tiny, tender French bush type haricot beans that are very popular in French cooking.

• The flageolet has a green pod about 3-inch long and small, kidney-shaped seeds, they range from creamy white to light green in colour.

• The secret of growing flageolet beans is that the seeds are removed from the pod when tender and just maturing.

How to grow Flageolet bean - Crop Rotation

• • Should follow a light or heavy feeder but not an other member of the Bean Family.

  • Should precede a heavy feeder, preferably a leafy one.

  • Should not be grown more than once every 5 years (7 preferably) in anthracnose infected soils.

  • It is recommended that the crop should be preceded by root crops or other light feeders or non leguminous green manures.

  • The recommended following crops are leafy crops such as green mustard or grain crops such as wheat. These can be grown as a green manure.

How to grow Flageolet bean - Position & Soil

• • The preferred soil type is a well drained loam rich in humus. However, any well-worked soil will grow a respectable crop as long as it is cared for correctly.

  • The preferred soil pH is 6.5, but a crop will prosper in a range of 5.8 to 6.7.

  • Direct sunlight is required, and the bean will not prosper in a high degree of shade.

Temperatures

• The chosen growing site must allow the following temperatures to be achieved.

  • Soil for germination requires a minimum 10°C (50°F), with an optimum temperature of 30°C (86°F). A range from 15°C to 28°C (60°F to 85°F) provides for best results in practice.

  • Soil temperature for best growth is in a range 21°C to 26.5°C (70°F to 80°F).

  • The air temperature during the day should be in the range of 15°C to 26°C (60°F to 80°F).

  • The air temperature at night is not that significant, providing it is above 10°C, and preferably above 15°C.

How to grow Flageolet bean - Soil Preparation

• • Apply a well rotted manure or compost application in early spring if necessary.

  • Till the manure into the soil, digging to a spade depth.

How to grow Flageolet bean - Sowing seed

• • It is good practice to inspect samples before sowing any bean cultivar for the first time by spreading all the seeds on a dry, clean, surface of a contrasting colour. Any seed looking off colour or beige or brown (in the case of Flageolets) or broken should be discarded and preferably burnt.

  • The seed examination limits the chances of sowing seeds that have no chance of success, it saves space and may even help in the prevention of diseases. This technique combined with the roguing of sick looking seedlings later on should ensure that the final produce is of top quality.

  • Sowing in line facilitate this later trick greatly. The most deadly diseases are the viruses so removing and burning any plant with mottled leaves will reduce the risk of spreading any such disease, whether the colouration is due to the mosaic virus or nutritional deficiencies.

  • The optimum sowing rate: 100 seeds per 10 m row.

  • Either sow seeds in line, 3 to 4 cm between seeds, 40 cm between rows or in groups of 3 to 6 seeds spaced 30 to 40 cm apart.

  • The first method suits best seed production as it facilitates roguing, the second technique is best suited to cropping but will not suite mechanical sowing.

  • Sow outdoor only, in the open or under clear plastic film which will be removed later.

  • Sow once the soil is warm enough. This is essential for a quick start, free of disease and pest problem.

  • 2 weeks after last frost to 4 months before the first expected one (based on averages) is a good guide.

  • Spacing successive sowings every 2 to 3 weeks is especially useful for extending the picking period of fresh seeds.

  • Sow the seeds 2 to 3 cm deep, slightly shallower in very heavy soil.

  • The time taken from sowing to germination is 4 to 10 days.

  • The time taken from sowing to harvest is 52 to 120 days depending on the cultivar and whether the seeds are harvested fresh or dried.

  • The average germination rate you can expect is 85% after 3 year storage.

  • Previous year seeds kept in good conditions can have a 98% success rate.

How to grow Flageolet bean - Care & Cultivation

• • Hill up plants as soon as they are large enough (install optional wires on either side of each row for later support).

  • Mulching reduce weeds and the incidence of anthracnose, because pods and soil are not in contact.

  • Hilling up and weeding should be limited to the early stage of growth so as not to damage surface rootlets.

  • Weed control is best performed by mulching under plants, and shallow cultivation between rows.

  • Foliar feeding may be used once every two weeks, in early morning.

  • A sprinkling of wood ashes on the surface after sowing is preferable to liming.

  • Soil must be moist enough during the first 2 weeks, during pollination and pod swelling. Irrigate more if necessary at 2.5cm (1 inch) per week.

How to grow Flageolet bean - Companion Planting

• • Corn, pumpkin, lettuces, Celery, Cucumber.

How to grow Flageolet bean - Diseases and Pests

• • Major diseases affecting beans are Anthracnose, Mosaic virus, other viruses, Black root, Botrytis, Summer death.

  • The most efficient disease control is using disease free seeds.

  • Roguing plants showing any symptom of disease may help towards achieving this when producing seeds for sowing.

  • Crop rotation is essential if disease is a problem, and is preferred to avoid such problems..

How to grow Flageolet bean - Harvesting

• • Average seed yield varies with cultivars from 10 to 15 kg of dried seeds per 100m row, 16 to 50 pods per plant, 2 to 8 seeds per pod.

Fresh seed production

• • Pick pods from the plants when seeds are fully formed, as one would for peas, and most pods are still "relatively difficult" to open (although part of the suitability to green-shelling of some cultivars / types such as the Flageolet is that they are easy to shell).

Semi-fresh (demi-sec) seed production

• • Pull up whole plants when about 80% of pods carry plump seeds and hang in a well ventilated shed away from light. Pick pods as soon as convenient. Pods are then easily opened.

  • Pods containing semi-dried seeds can also be picked directly from the bushes outside but they cannot wait then or the seeds may loose their green colour.

  • An other advantage of lifting the whole plants is that it liberates the ground for other crops.

  • For seed stock the plants should be picked when the pods have begun to dry and change colour.

  • Do not pick from the plants outside during wet weather or when plants are wet for water can carry diseases from plant to plant via the hands of the picker.

Snap beans

• • Although it would be a waste to pick the pods when young (at the snap stage) if such was the intention of the grower, picking would need to be carried out at least every two days.

Harvesting next years seed

• • Other varieties of Phaseolus vulgaris must be spaced at least 30m apart with a tall barrier in between.

  • The pods should preferably mature on the plants in place and the seeds should be collected only from non-diseased specimens.

  • Seeds with anthracnose symptoms (spots) should never be sown when intending to grow seed stock ie re-sowing.

How to grow Flageolet bean - Storing & Preserving

• • Fresh seeds keep only a few days in the best conditions (relative humidity 85 to 90%).

  • Freezing is possible but nutritional value declines.

  • Dried seeds for human consumption are stored like those for sowing in dry cool conditions.

  • Semi dried seeds can be stored either way but will become dried if stored too long in dry condition

References:

1. Michel H. Porcher, 2000 - 2010, Introducing the Flageolet bean, Part of the M.M.P.N.D. published by the University of Melbourne, Australia.