1, black beans usually about 30 hours black bean seedlings up to 3 ~ 4 cm, the foam box will be placed on the bracket or on the ground, take a rootless bean sprouts (2 ml) to 1 ~ 2 kg of water, the sprouts to spray to reduce the production of lateral roots and root hairs and increase the area of cotyledons.

2, black bean seedling height of 8 ~ 9 cm take a thickening agent (2 ml) 1 ~ 1.5 kg of water, the sprouts spray, in order to inhibit the elongation of the true leaves, so that the stem thickened to become brittle and reduce the fiber content and so that the bean plump, bright green and glossy, improved commerciality.

3, black bean seedlings throughout the production process of water spray 2 to 4 times a day, if the temperature is high, humidity, more spray, and vice versa, less spray, less spray in the pre-growth period, the late growth of the rapid growth of water demand, should be more spray.

4, the production of black bean seedlings should be timely culled moldy seed grains, so as not to cause the center of the disease, infestation of the surrounding bean seeds. Foam box reuse should be thoroughly disinfected with rot fungus clear, and burst in the sun for 3 to 4 hours.