1. Root: root is divided into main root, lateral root and fibrous root. The main root is deep and grows vertically into the ground. It also has lateral roots and grows horizontally. There will be fibrous roots on the lateral roots.
2. Stem: the stem is upright with rough surface and bristle. Later, it will be lignified and hollow inside. The color of the plumule at seedling stage can distinguish its varieties.
3. Leaves: the leaves are divided into cotyledons and true leaves. There is only one pair of cotyledons. The number of true leaves is large, and they are opposite or alternate, with bristles on the surface.
4. Flowers: there are two kinds of flowers on the top of sunflower stem. In the outer circle of the disk, there are ligulate flowers, and in the inner part of the disk, there are tubular flowers. The color is yellow
5. Fruit: the seeds are long, with black and white stripes on the outside and edible cotyledons inside, commonly known as melon seeds.
1. Temperature: sunflower does not require high temperature, as long as it is higher than 10 ℃, it can grow healthily.
2. Water: there is little demand for water during the growth period of sunflower. But at the beginning of bud stage, more water is needed, less water will reduce the number of seeds.
3. Light: sunflower is commonly known as sunflower, which is indispensable for all stages of growth. Sufficient light can guarantee its robust growth, vigorous stems and leaves, and full seeds.
