When does the sunflower blossom?
Sunflowers are usually sown in March to April and bloom in July to August. Sunflowers can bloom all year round, and the secret is "accumulated temperature", that is, plants can bloom as long as they accumulate a certain temperature during their growth. It usually takes 6-9 days for a sunflower disk to be put into a tubular flower from a tongue-shaped flower, and it blooms from the next day to the fifth day, and the number of flowers in these four days accounts for about 75% of the total. Most flowers bloom at 4 ~ 6 in the morning and pollinate and fertilize the next morning, and the unfertilized branches can remain unchanged for 7 ~ 10 days.
Growing environment of sunflower
1. Temperature: Sunflower is a kind of crop that likes temperature and cold. Strong adaptability to temperature, strong low temperature tolerance of seeds. When the local temperature is above 2℃, the seeds germinate and take root at 4 ~ 5℃, and when the ground temperature reaches 8 ~ 10℃, the seeds can meet the needs of germination and emergence. As long as the temperature of sunflower is not lower than 10℃, the whole growth process can grow normally.
2. Moisture: Sunflower is a kind of crop with high water consumption, with tall plants and dense leaves, and its water absorption rate is 1.74 times that of corn. However, because its growth and development are synchronized with local rain and heat, the contradiction between water supply and demand is not prominent, and the requirements for water in different growth stages are very different. There is not much water demand from sowing to budding, and it is the peak from budding to flowering, and there is also more water demand from flowering to maturity.
3. Illumination: Sunflowers are short-day crops and are not very sensitive to sunlight. Like plenty of sunshine, its seedlings, leaves and disk have strong phototropism. Adequate sunshine and strong seedlings can prevent blind growth. Adequate sunshine in the middle growth stage can promote the vigorous growth of stems and leaves, normal flowering and pollination, and improve the seed setting rate. In the late growth stage, the sun is full and the seeds are full.
4. Soil: Sunflowers have low requirements on soil, and can grow on all kinds of soil, from fertile soil to arid land, barren land and saline-alkali land. Not only has strong saline-alkali resistance, but also has salt absorption performance. At the same time, sunflower has developed roots and strong drought resistance. Moreover, the roots and stems of sunflower have developed aeration tissues, which are very resistant to waterlogging.
Sunflower is named because its flowers often face the sun. Many people like this kind of flower in life. When and how long do sunflowers bloom? Let's take a look!
Growth cycle of sunflower
1, seedling stage: Sunflower is called seedling stage from emergence to budding, which generally takes 35-50 days, and summer sowing takes 28-35 days. This period is the stage of leaf and flower primordium formation and floret differentiation. Sunflower seedling stage is the stage with the strongest drought resistance, with slow growth of aboveground parts, rapid growth of underground roots and rapid formation of strong roots.
2. Germination period: Sunflower generally takes about 20 days from germination to flowering, which is the period when vegetative growth and reproductive growth are carried out at the same time, and it is also the most vigorous stage in life. During this period, the most fertilizer and water are needed, accounting for 40 ~ 50% of the total fertilizer and water demand. If the demand for water and fertilizer cannot be met in time, the output will be seriously affected.
3. Flowering period: Generally, it takes 6-9 days for a sunflower disk to bloom from a tongue-shaped flower to a tubular flower, and it blooms from the next day to the fifth day, usually opening at 4-6 in the morning and pollinating the next morning. Unppollinated branches can last for 7-65,438+00 days, but the seed setting rate of self-pollination is only about 3%, and the seed setting rate of cross-pollination is high.
4. Maturity: The maturity of sunflower refers to the period from flowering to maturity, which is 25-55 days in spring and 25-40 days in summer, with differences among different varieties. The seed formation period is about 15 days after flowering and pollination. Sunflower maturity needs sunny weather, large temperature difference between day and night and suitable soil moisture.