1、 What season is sunflower

Sunflower is an annual herb, and its flowering period will vary according to different varieties. But it usually blooms in summer and autumn, belonging to summer flowers. If it is sown from March to April, its flowering period is from July to August and its maturity period is from August to September. There are two kinds of flowers on the disk: tongue flower and tubular flower. Tongue shaped flowers have 1-3 layers, which are inserted around the edge of the disc and are asexual flowers. Tubular flowers are located on the inner side of tongue flowers and are bisexual flowers. The size and color of the flower disc vary from variety to variety, generally orange, light yellow and purplish red

2、 How to plant sunflowers

1. Planting time: sunflower is best planted from March to April. At this time, the temperature and humidity are suitable for planting, and the survival rate will be higher

2. Planting land selection: the planting land can be selected in the place with flat land, medium fertility, convenient irrigation and low soil viscosity

3. Temperature: the suitable temperature for sowing is between 18-25 ℃. It is usually planted after the temperature rises to 20 degrees, and the seeds will begin to germinate in about 5-7 days. When the ground temperature is above 2-5 ℃, the seeds can germinate stably. When the ground temperature reaches 8-10 ℃, the seeds can germinate and emerge. Sunflower can grow normally as long as the temperature is not lower than 10 ℃ in the whole growth process

4. Water and fertilizer: the requirements for water and fertilizer at different growth stages will also be different. Between seedling stage and budding stage, the demand for water and fertilizer is low. The demand for water and fertilizer in bud stage and flowering stage will increase significantly, so as to meet the demand for water and fertilizer in time, otherwise it will seriously affect the yield. The demand for water and fertilizer in the mature stage is also high, but it is not as high as before. It is necessary to appropriately reduce the amount of watering and fertilization

5. Illumination: sufficient sunlight is needed, and its seedlings, leaves and flower plates have strong phototropism. Sufficient sunshine can prevent overgrowth, promote vigorous growth of stems and leaves and improve seed setting rate