When do "Compositae" sunflowers usually blossom? When does it blossom most? When is the best time to sow seeds?

Sunflower is an annual herb of the genus Asteraceae. It is cultivated in China. Sunflower seeds, called sunflower seeds, are often fried and eaten as a snack. So when do sunflowers usually blossom? When does it blossom most? When is the best time to sow seeds? The details are as follows:

Sunflower flowering time

Sunflowers are usually sown in April, flowering from July to August, seed maturity from August to September, and flowers bloom at 4: 00 a.m. to 6: 00 a.m.

Sunflowers can be used in all seasons, mainly in summer and winter. The florescence can reach more than two weeks. In addition to being similar to the sun in appearance, sunflower has bright and generous flowers that are suitable for ornamental decorations. Her seeds are of more economic value. They can not only make popular sunflower seeds, but also extract high-grade edible sunflower oil with low cholesterol. Sunflower varieties can be divided into "general ornamental" varieties or "edible" varieties, the general ornamental varieties are characterized by short plants, usually no more than half a meter, so they are suitable for planting in pots, while edible varieties are taller and taller. Planted in the soil of the general open-air nursery, it can grow to more than 2 meters. Sunflower grows very fast and usually blossoms after about two months. Its flower pattern can be divided into single, double or single or multiple flowers, and its flowering period is quite long and can reach more than two weeks.

Sunflower is not strict on soil and can grow on all kinds of soil, from fertile soil to dry land, barren and saline-alkali land. Has a strong ability to tolerate salt and alkali.

Sunflowers are usually sown in a few months

Planting methods of sunflower

Part I: seeds

The cultivated seeds are soaked in warm water and then planted in the soil with the tip of the seed facing down. it can germinate in about 4-5 days.

Part two: sowing

1. The sowing date can be sown when the temperature of 125px soil layer is 5 ℃. The basic principles of sowing date selection are: first, according to the law of saline-alkali occurrence, appropriate early or late sowing to make seedlings avoid saline-alkali damage; second, spring or summer sowing according to the growth period of varieties; third, adjust sowing date according to the law of disease incidence to avoid disease-prone seasons; fourth, adjust sowing date according to growth characteristics to avoid high temperature weather above 28 ℃ during flowering and filling period.

two。 The germination rate and emergence rate of sunflower were lower than that of oil sunflower, and the top soil ability of sunflower was also lower than that of oil sunflower. In order to ensure the number of seedlings, the actual sowing rate should be 10% higher than the calculated sowing rate. The ability of self-regulation of sunflower is very strong, if the planting density is high, the disk is small and the grain is small; when the density is small, the disk is large and the grain is also big. Under the premise of ensuring both yield and commodity, it is appropriate to keep the number of seedlings in 667m2 at about 3000, row spacing 60-1750px, plant spacing 30-875px. The sowing rate is determined according to the characteristics of varieties and cultivation requirements. Generally, manual sowing needs 600 grams per 667 square meters and machine sowing needs 700 grams.

3. The growth period of sunflower with seed fertilizer is longer, and the plant is tall. The amount of seed fertilizer is 8 kg per 667 square meters of hole or strip application of diammonium phosphate, or 10 kg of three-material phosphate fertilizer.

4. When sowing, the soil moisture should be better, and the depth of 3-100px should be better. The sowing method is:

① artificial or mechanical planting, sowing on demand or trenching

② precision on demand, each acupoint 1 Murray 2 tablets. In arid areas, the method of deep trenching and shallow covering can be adopted to sow seeds on wet soil with better soil moisture.

Part III: sowing conditions

The sowing time of sunflower: March to April.

The suitable temperature for sowing is 18-25 ℃.

Sprouting time: 5-7 days.

Sowing method: sowing on demand, covering with soil about 25px, flowering about 50-80 days after sowing, slightly different due to different varieties. Bad symptoms.

Part IV: field management

Field management is an important link to cultivate strong plants and achieve high quality and high yield. As the saying goes, "three minutes, seven minutes."

The main results are as follows: 1. Sunflower is a dicotyledonous crop, which is difficult to emerge from the top soil, coupled with the low quality of soil preparation and sowing, or hardening of surface soil after sowing, or damage caused by diseases, insects, rats, finches, etc., are easy to cause lack of seedlings and broken ridges. In order to ensure the whole seedling sowing, the field must be checked line by line during the seedling emergence period; if the seedlings are missing in a row, they should be replanted in time, and the seeds should be soaked to promote budding and whitening. Lack of seedlings should be dense and sparse, transplant with soil (pay attention to the sunny orientation of the seedlings), pour good root water, the survival rate can generally reach more than 95%. Some insurance seedlings can also be raised to meet the needs of the whole seedling.

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