How to plant the seeds of Compositae sunflowers? When will the seeds be sown? What are the methods?

Sunflower is an annual herb belonging to the genus Helianthus of Compositae. China is cultivated. How do you plant your seeds? When to sow? What are the planting methods? Sunflower planting base in Shanxi Province showed that sunflower had strong ability of low temperature tolerance at seedling stage and mature stage. The seeds began to expand and germinate at 2℃-4℃, germinated at 4℃, germinated at 5℃, and met the needs of normal germination at 8℃-10℃. Sowing time is generally in late March to mid-April, direct seeding or seedling transplanting can be done, planting density is 65 cm ×60 cm, one plant per hole.

How do sunflower seeds grow? (potted plant)

Pre-sowing treatment:

1. Seed selection before sowing: seed selection before sowing can effectively improve the emergence rate except for the impurities in the grain.

2. Sunning seeds before sowing: Select sunny weather before sowing, spread seeds for 2~3 days, reduce seed moisture, increase body temperature, strengthen enzyme activities in seeds, promote post-ripening, enhance vitality, improve germination potential and germination rate, which is conducive to rapid germination after sowing and uniform emergence.

3. Seed dressing with pesticide: In order to prevent the harm of underground pests and the occurrence of sunflower diseases and improve the seedling rate of sunflower, it is best to mix 600g of zinc mixed with seed fertilizer evenly for soil treatment or seed dressing with abamectin or phoxim emulsifiable concentrate, water and seeds in a ratio of 1:40:500. When dressing seeds, spray while stirring, so that the solution fully soaks the seed coat, and timely dry sowing.

Soaking germination: Soaking germination can shorten the water absorption and expansion time of seeds in the soil, sprout early, strive for the number of growth days, mature early, and avoid the loss of production due to freezing damage after autumn. The specific methods are as follows: warm water soaking: sunflower seeds are soaked in warm water at 18℃ for 6~12 hours, edible seeds are soaked for 6~8 hours, oil seeds are soaked for 6~8 hours, and seeds can be sown after being taken out and dried to 70%. If you need to germinate, take out the soaked seeds and put them in plastic bags. Put them in a warm room and stack them overnight. When the seed coats of some seeds begin to show white, most seeds begin to germinate and can be sown (they must be sown in plots with good moisture content, otherwise they are easy to sprout).

After germination:

1. When sunflower seeds germinate and emerge from the soil, they can be transplanted into large pots when they open their cotyledons. After transplanting, we should irrigate enough root fixing water, and we must irrigate it thoroughly. It is recommended to put it indoors where there is sunshine. If it is to be placed under the sun, it is necessary to water it frequently.

When about 3 to 4 pairs of true leaves have grown, spray some potassium dihydrogen phosphate on the leaves every few days to promote plant growth. Sunflower in the growth of its fertilizer, attention must be decomposed organic fertilizer at this time.

What are sunflower planting methods?

1. Land selection: deep soil layer, flat land, irrigation and drainage supporting facilities, rotation period of more than 3-4 years, and continuous cropping is strictly prohibited.

2. Soil preparation and fertilization: fine soil preparation, full base fertilizer, no stubble before sowing, heavy base fertilizer, deep seed fertilizer. Deep ploughing in autumn is 20- 625px, farm manure is applied 1000- 1500kg per mu, autumn irrigation should be carried out in due time on the basis of base fertilizer in autumn, and on the basis of timely harrowing in winter and spring, leveling and weir reduction (1-1.5 mu/block) before sowing should be carried out, so as to achieve uniform ground level, soil fragmentation and moisture content. 10-15kg of diammonium phosphate, 7-8kg of potassium fertilizer (potassium chloride or potassium sulfate), or ternary compound fertilizer of nitrogen, phosphorus and potassium are deeply planted in the edible sunflower rows before sowing.

3, before sowing should be 2-3 days of sun, with 40% zinc phosphorus 150 ml, mixed with water 5- 7.5 kg, seed dressing 25-30kg, to prevent underground pests. Soak seeds with 500 times solution of carbendazim for 6 hours, or dress seeds with clean sclerotium and methyl thiophane, etc., with the dosage of 0.5-0.6% of seed quantity to control sclerotium disease.

4. Dibble sowing or furrow sowing is adopted. The sowing depth in clay land is 82.5px, and the sowing depth in sandy loam land and sandy land can reach 4- 150px. Sunflower sowing date is generally determined early spring sowing, sowing methods to artificial hole sowing mainly. Hole sowing method can be according to the requirements of the plant spacing point seeds, sowing depth of about 5 cm. Generally, the planting rate of hole sowing is 1-1.5 kg per mu, 4-5 seeds per hole, wide and narrow row sowing is implemented, the large row spacing is 100 cm, the small row spacing is 50 cm, the plant spacing is 60 cm, and about 1400 seedlings are reserved per mu.