Beans are a member of the legume family. Legumes are plants that produce seed pods which split in half to release seeds. Beans are very easy to grow and are a staple in many vegetable gardens. They are very vulnerable to frost damage. Different varieties of beans include climbing string beans, climbing string-less or French beans, bush beans and broad beans.
Seed and Germination
Bean seeds may be planted in their dried form, but this will slow germination speed. To achieve the quickest possible germination, soak the seeds in water for 12 to 24 hours before planting, allowing them to rehydrate. If you presoak the beans and water them evenly and regularly, germination will occur in 10 to 16 days, depending on weather.
Once the seedlings break through the soil, two small, pointed leaves unfurl. These leaves continue to grow as the roots more fully develop in the soil. If the seedlings are in trays, they must be kept protected from the cold, preferably indoors or in a greenhouse. Do not plant bean seedlings outside until all chance of frost has passed, as they are very susceptible to even mild frosts. If touched by frost, the plants will definitely be stunted and will most likely die. The exception to this is broad beans, as these are much hardier than other beans; some varieties, such as Aquadulce, can be planted in mid-winter for an extra early crop the following spring.
Once all danger of frost has passed and your young seedlings are in their final growing location, bush varieties will begin to fill out, producing much more foliage, and will increase in height to around 1 foot. Broad beans will begin to grow upward, and their stems will thicken. Climbing beans will shoot at least one long trailer, which will produce additional leaves as it grows. Climbing beans need supports to climb. You can use “tepee” frames made from bamboo or willow canes, or, if you are also growing sweet corn, you can plant several bean plants around the base of each corn stalk. The beans will climb the corn without damaging it and will save space.
Flowers will form and, if pollinated, will die back, and a tiny bean pod will be visible. The pods of French beans and bush beans should be harvested before they begin to soften and thin. When harvesting runner or string beans, the pods should be pale green and smooth. Pods that are tough and have rough edges will have an unpleasant “stringy” texture when cooked, but the beans may be dried and used as seed for next season, or for cooking over the winter.
The plants will die back around the time of the first frost. It is not practical to save seed from broad beans, as they cross-pollinate very easily. To save seed, you need to isolate your beans from any other broad bean varieties in a half-mile radius, unless you wish to create a new cross-variety bean; however, this may not produce edible pods. You can save string and runner bean seeds if you grow only one variety, and any French and bush bean seeds may be saved, as these do not usually cross-pollinate.