Clockwise from above: Climbing French beans (Phaseolus vulgaris) ready for harvest; Podding out the beans from their shell; Dried pinto beans.
The ‘common bean’ Phaseolus vulgaris – phaseolus being Greek for bean and vulgaris Greek for common – covers both green beans (French beans) and dried beans such as pinto, navy, kidney and borlotti.
Although there are records of bean cultivation in Mexico in 4000 BCE, the plants seem to have originated from the temperate regions of South America. The Incas of Peru are thought to be the domesticators of beans.
Some beans are grown to be eaten green when the pods are tender (green beans or French beans) and others are eaten dried (kidney, navy). Green beans have either no parchment (inner skin) in their pods, or a very thin one, and the beans for drying usually have a thick parchment. Apart from the green beans being left to mature on the bush, the seed-saving techniques for both green and dried are very similar.
Plant the seeds directly in the position they are to grow because they do not survive transplanting very well. Dwarf (bush) beans need a less-rich soil than climbers because they have lower yields and are in the ground for a shorter period. A climbing bean can yield up to three times more than a dwarf bean.
Saving The Seeds
Accidental hybridisation (crossing) rarely occurs because pollination happens mostly before the bean flower opens (ie automatic pollination). This explains why so many gardeners have been able to keep their favourite strains pure for decades. Despite this, different climbing varieties are best planted two metres apart to ensure a 100% purity. It is also good practice to avoid planting two different varieties of climbing beans with the same coloured seed side-by-side, because they will be hard to sort at harvest.
Beans grown for seeds are grown the same as dry beans for home consumption, except that at an early stage those with leaf discolouration, bacterial blight or any other sign of disease should be rogued out. Select the finest individual plants and identify with a ribbon.
Traditional gardeners say that pruning the top of climbing varieties causes the lower bean cluster to grow larger. Some gardeners believe that seeds selected from the top of the bush will grow into plants with a predisposition to flower poorly at lower and mid-level.
If the weather is wet at harvest, the beans may be picked and dried progressively as they come to the yellow pod stage. With dwarf varieties, when the pods turn yellow-brown, the whole bush can be uprooted and hung in a dry, airy space. Leave all the pods on the bush to dry completely. Pod out the beans from their shells. If you have large quantities, hang them in hessian bags and beat them with a stick.
Assessment of the dryness of the seed needs to be made during the next stage. Test the beans by biting with a gentle pressure. No impression should be made. Discard blemished and shrivelled seeds. Usually you will need to dry them for a further one or two weeks.
Store them in airtight containers on a dry day. Weevils lay their eggs under bean seed coats and the seeds will be eaten when they hatch. Freeze the dried beans in a jar for 48 hours to kill weevils and their eggs. Coating with edible oil prevents weevil infestation. Bean seeds will last three years. Some will germinate if kept for several years, but not as vigorously. Bean seeds range from five to ten per gram.
Beans are the ‘meat’ for millions of people in the world. Combined with cereal and a small amount of seed oil, they make a complete meal. Green bean juice is a diuretic: one glass before breakfast is recommended. The cooking water from dry and green-shelled beans revives the colour in printed cotton fabrics when added to the wash.