Vigna unguiculata subsp. sesquipedalis

The Kilometre Bean belongs to the Fabaceae family without being a Phaseolus. So, despite its name, it is not a green bean in the strict sense. But it looks very similar: it produces green pods with a round section. It climbs up to 3 or even 4 metres (13 feet) in height like climbing varieties. Simply put, its pods grow exceptionally large in a lush garden where everything would be gigantic. They form long vines averaging 80cm (32in) in length, with edible pods and seeds. Like beans, the edible parts are directly related to the ripeness of the fruit when harvested.

The Kilometre Bean is particularly cultivated in tropical environments, especially in Asia. This plant particularly enjoys heat. Therefore, it should be planted in a very sunny and warm location. Sowing should be done as soon as the soil is adequately warmed.

By arranging bamboo stems in a teepee or Canadian tent shape, you can combine usefulness with aesthetics in the vegetable garden: you will obtain beautiful trellises that will form a green wall. Place several seeds in a hole at the base of each support. Each plant produces numerous yellowish-purple flowers, which will give way to a bountiful fruiting from July onwards.

Its very distinctive taste is a cross between that of green beans and asparagus. It is rather appreciated for its immature pods, as the flavour of the dried beans is rather mediocre.

Whether consumed for its pods or its seeds, beans are highly appreciated vegetables in gardens because they are very easy to grow. They are so punctual that gardeners know the exact date of their first harvest, which occurs 60 days after sowing.

Discovered in the New World and acclimatized in Europe from the 16th century onwards, beans have now become an essential legume in diets around the world. Native Americans cultivated them for their dried seeds, but it was the Italians who, in the 18th century, initiated the consumption of the whole immature pod.

The bean is a vine with indeterminate growth. Primitive varieties are all climbing and require support. Later, for practical reasons, dwarf varieties were selected, but all of them have tendrils that can wrap around a support.

The pods are usually green, sometimes yellow (butter beans), striped with red, or even amethyst. Among the varieties that are eaten when they are "fin" or "extra fin" (thin or extra thin), there are "haricots à filets" which have threads when ripe. Then the pod becomes parchment-like and loses its flavour. The "haricot mangetout" is generally more fleshy and can be eaten entirely, both the seeds and the pods, even when ripe. The more recently created "filet - mangetout" beans can be consumed when young as "extra fin" until they become more fleshy like a "mangetout", as they do not form threads.

Among the "à écosser" varieties (those whose seeds are consumed), the harvest of fresh beans is distinct from the harvest of dry seeds, which occurs 90 days after sowing.

The immature green pods are rich in vitamins A, B9, and C, as well as trace elements and minerals. Dry beans are also very rich in vitamin C, trace elements, and especially plant proteins.

Harvesting: The harvest of fresh beans or young pods begins 60 days after sowing. For fresh beans, it should be done before the pods start to dehydrate and develop wrinkles. The beans should barely have taken on their color. For the consumption of pods, the harvest should take place every 2 or 3 days, both at the "fin" and "extra fin" stages for filet beans. The harvest of dry beans is done by cutting the entire plant, which is then hung in a dry and airy place. They can be shelled as needed.

Storage: Freezing pods is the most common method of preservation today. To do this, trim the ends, wash the pods, blanch them for 5 to 6 minutes in boiling water, then plunge them into cold water before drying them with a clean cloth. Once placed in bags, the beans can be placed in the freezer at -18°C (-0.4°F). However, canning is regaining its popularity among an increasing number of consumers due to the inherent taste qualities of this preservation method. Like freezing, trim the ends, wash and blanch the beans, then plunge them into cold water. Place them in jars and fill with salted boiling water. Seal the jars and sterilize in a pressure cooker or with a sterilizer for 1 hour and 30 minutes over medium heat. Completely cover the jars with water after tightening the lids.

Dry beans: When fully dry, bean seeds can be stored for up to a year if kept in good conditions, such as in airtight jars.

Gardener's tip: Beans, like all members of the Fabaceae family, have the ability to fix nitrogen from the air into the soil through plant-bacteria symbiosis. They have the ability to regenerate soils. Beans can be included in crop rotation after burying green manure. In Central and South America, beans are traditionally associated with squash and corn, forming a beneficial triad. This association is locally known as Milpa. Beans also pair well with eggplants, carrots, cabbage, potatoes, and radishes, as they mutually protect each other. Avoid the presence of alliums or fennel, as their growth inhibits each other.

A spray of nettle manure allows for effective control of aphid attacks and strengthens the plants that benefit from it.