When is the sunflower blooming?

When is the sunflower blooming? I believe many people have not thought about this question, so let's look for the answer below with this question.

Sunflower is a head, growing at the top of the stem, commonly known as the disk. Its shape can be divided into three types: protruding, spreading and concave. There are two kinds of flowers on the disk, namely, ligulate flowers and tubular flowers. Ligulate flowers 1-3 layers, inserted on the periphery of disk, asexual flowers. Its color and size vary from variety to breed, with orange, yellowish and purplish red, which can attract insects to come to collect honey and pollinate. Tubular flowers, located on the inside of ligulate flowers, bisexual flowers. The colors of Corolla are yellow, brown, dark purple and so on.

When is the sunflower blooming?

The main flowering period of sunflower is from mid-July to mid-and late August. The florescence can reach more than two weeks.

The ligulate flowers of 75% of the plants in the field bloom, that is, the flowering stage. It usually takes 6-9 days for a disk to open from a ligulate flower to a tubular flower. The inflorescence is in full bloom from the second day to the fifth day. The number of flowers in these four days accounted for about 75% of the number of flowers. Most flowers bloom at 4-6 o'clock in the morning, and the next morning they are pollinated and fertilized. Unfertilized branches can remain intact for 7-10 days. The seed setting rate of self-pollination of sunflower is very low, only about 3%, while the seed setting rate of cross-pollination is high.

Matters needing attention in sunflower maintenance

The main results are as follows: (1) nitrogen deficiency of sunflower: the growth of sunflower is not fast at seedling stage, the plant is slender and thin, the leaves are small and thin, showing yellowish green or light green; in the middle stage of growth, the lower leaves turn yellow in the early stage, the flower disk is small, and the growth of vegetative organs becomes worse, resulting in premature senescence of plants.

(2) phosphorus deficiency of sunflower: stunted development of plants and flowers.

(3) potassium deficiency of sunflower: the plant grows slowly, the leaves turn yellow, and there are brown spots on the leaves, which finally dry up into thin pieces and fall off, and the oil content decreases.

(4) calcium deficiency of sunflower: stem bending appeared before and after flower formation.

(5) Sunflower is sulfur deficient: the leaves and inflorescences are light, the internodes are short, and the plants are short.

(6) magnesium deficiency of sunflower: chlorosis between veins.

(7) Manganese deficiency of sunflower: the leaves showed reticular chlorosis.

(8) Boron deficiency of sunflower: after cotyledon opening, the growth point was damaged or died or the axillary bud germinated to form a plant, the growth was abnormal, the plant was short, and the stem had brown hook longitudinal band marks. After the formation of the disk, the stems supporting the disk lose the ability to turn with the sun, some with their heads down, others with their heads facing up, the lower old leaves are thick and dark green, the upper leaves are small and curly, the mesophyll is green, and the veins protrude.

(9) Zinc deficiency in sunflower: growth was blocked and upper leaves were yellowed and necrotic.

(10) Iron deficiency of sunflower: the upper leaves turn yellow and the veins are still green.

(11) Copper deficiency in sunflower: deformity of upper leaf and Corolla.

The management method of sunflower budding stage:

At the top of the sunflower, there is a star with a diameter of 1 centimeter, commonly known as budding. From bud to flowering, it usually takes about 20 days, which is not only the period of vegetative growth and reproductive growth, but also the most exuberant stage in life. During this period, sunflowers need the most fertilizer and water, accounting for about 40% and 50% of the total amount of fertilizer and water needed. If the demand for water and fertilizer can not be met in time in this period, the yield will be seriously affected.

Management methods of sunflower flowering period:

The ligulate flowers of 75% of the plants in the field bloom, that is, the flowering stage. It usually takes 6-9 days for a disk to open from a ligulate flower to a tubular flower. The inflorescence is in full bloom from the second day to the fifth day. The number of flowers in these four days accounted for about 75% of the number of flowers. Most flowers bloom at 4-6 o'clock in the morning, and the next morning they are pollinated and fertilized. Unfertilized branches can remain intact for 7-10 days.

The seed setting rate of self-pollination of sunflower is very low, only about 3%; the seed setting rate of cross-pollination is high. However, if the temperature is high, Rain Water is more, the humidity is high, the light is insufficient, and the soil is dry, the seed setting rate will be greatly reduced.

Therefore, adjusting sowing date, timely fertilization and watering, prevention and control of diseases and insect pests, and taking measures such as bee release or artificial pollination can improve the seed setting rate.

Management methods of sunflower maturity:

From flowering to maturity, 25-55 days in spring and 25-40 days in summer. There are differences among different varieties. The stage of grain formation is about 15 days after flowering and pollination. It needs sunny weather, large diurnal liquid temperature difference and suitable soil moisture.

The above is the whole content of when the sunflower blossoms are summarized for you. I hope this article can help you. Please continue to follow us.