Germination is the beginning stage when a young plant starts to grow from a seed. Gardeners watch the areas where they plant dry, shell or green beans for several days while waiting for the young green plants to emerge. During this waiting period, the process of germination is taking place within the garden soil.
When the soil is frost-free and warm, the gardener prepares the garden for the type of beans he wishes to grow. On day 1, he plants the seeds, covers them with soil and adds water to the soil. The outer surface of the hard seed softens with the moisture provided by the water. The embryo inside of the seed shell releases an enzyme which sets off the growth process by day 3 or 4. Oxygen is taken in when the enzyme activates the plants need for it. The seed swells with the growth of the embryo and splits open. A root emerges and grows downward, securing the seed in the soil. This primary root gives the embryo access to nutrients and water in the soil, aiding the growth process.
The hypocotyl arch (the bent shoot that will develop into the plant's stem) pushes up through the garden soil on days 4 to 7 (and up to 10, according to soil and weather conditions). This green shoot is bent in a tight arch shape. The cotyledons (embryo leaves) protect the epicotyl (primary leaves) as the sprout emerges from the soil.
After the hypocotyl arch emerges from the soil, it begins to unfold, reaching toward the light of the sun. The protective cotyledons move apart and the epicotyl leaves start to unfurl within a day or two. The primary root grows into a substantial root system that absorbs nutrients from the soil. The plant continues to grow, establishing itself in the soil with the root system, while drawing upon the light. New leaves start to grow as the plant begins to gain height, with several sets established by day 21.