What is the height of tomatoes after they grow leaves?

I. Culture conditions

Processing tomatoes are suitable for planting in slightly sticky sandy loam, avoiding saline-alkali land and plots with heavy pesticide residues (such as plots with Le 'an, Fuleling and herbicides). The suitable temperature for germination needs to be between 28℃ and 30℃, and there are about 3000 ~ 3500 plants per mu.

Second, ridging

1. Before ridging, apply 3 ~ 5m3/mu of decomposed farmyard manure, 50kg/mu of phosphate fertilizer and 20kg/mu of ammonium nitrate to the selected plot. Transplanted tomatoes were ridged and covered on April 20, and planted in early May. Sow the direct-seeding tomatoes 10 days before sowing, and the sowing time is from April 10 to May 20th.

2. Rising standard: the ridge width of the processed tomato is 70-80cm, the height is 15-20cm, and the ditch width is 40-45cm. After ridging, the ridged soil should be made into a width of 100- 120cm.

Third, cultivation techniques.

1. Transplanting cultivation techniques of tomato seedlings

(1) Seedbed design (1) Seedbeds should be high in terrain, sheltered from the wind, sunny and easy to irrigate. A plot without solanaceae crop rotation for 5 years. The net area of seedbed should be kept at 20m2/mu; (2) After leveling, apply 2kg/m2 of diammonium phosphate, 20kg/m2 of decomposed farmyard manure, 5kg/m2 of plant ash and 8~ 10g/m2 of carbendazim, and sow after solidification; (3) When sowing, soak in 1.5% formalin solution for 15 ~ 20 minutes, and then close the seeds for about 2 hours. Sow the soil after thawing, use 8m×8cm plug, 2 grains per hole, 0.5cm sand or 1cm nutrient soil, and water after sowing.

(2) Seedbed management (1) After sowing, the shed remained relatively closed with high temperature and humidity. The temperature is controlled at 28-30℃. When the temperature in the shed reaches 18℃, lift both ends of the shed roof to let the wind out. The outdoor air temperature is controlled between 20 ~ 24℃, and the night temperature is controlled between 10 ~ 15℃. (2) Hardening seedlings: When the seedlings grow to 5 leaves, shallow irrigation will help to form fiber roots, and no watering will be done later. The seedlings are dark green and purple, with white roots, large and thick leaves and a height of less than 25 cm.

(3) Planting, watering and shading 7 days before planting and sowing. When planting, plant the seedlings on a dry pond at a distance of 10cm from the edge with a spacing of 45cm. Plum blossoms are planted in the second row, and the planting depth should not exceed cotyledons 1 cm. The hole in the seedling hole should be widened as far as possible, compacted with soil to prevent hot air from squeezing out and burning seedlings, and planted together with water.

2. Cultivation techniques of direct seeding tomato

(1) After ridging, seeds can be soaked in April 15, and then they can be sown by breaking the film, with the plant spacing of 45cm, and planted in plum blossom shape in two rows, with 4-5 seeds per hole. The upper cover is 0.5cm thin sand. Water once after sowing, the water surface is higher than the dry pond.

(2) Removing seedlings and supplementing seedlings: when the direct-seeded tomato has 2-3 real leaves, the seedlings can be removed, and the redundant seedlings can be transplanted into the missing seedlings.

3. Tian Tuan management

① The planting of processed tomatoes follows the principle of "less watering and more fertilization". It usually takes 15 to 18 days to water. Topdressing is carried out several times. Apply urea 10kg/ mu after the first delay of emergence to promote seedling growth, and apply 20k g/ mu diammonium phosphate or 30k g/ mu special fertilizer for tomato to promote fruit expansion at the second fruiting stage. After each tomato is harvested, 10kg/ mu of ammonium nitrate should be applied together with watering. When used, it should be far away from plants to prevent seedling burning.

② Prune and stubble when the lateral branches of the first inflorescence grow to 5- 10 cm. All side branches should be removed in time. When the first ear fruit reaches the green mature stage, the lower leaves can be removed.

③ Shelving: After flowering and fruiting, the fruit seedlings should be fixed on the shelf in time around June 15. Don't pour the seedlings in the ditch to reduce the chance of disease and prevent rotten fruit.

④ prevention and control of fruit drop: spraying 2,4-d10×10e-6, PCPA 25 ~ 50× 10e-6 and tomato high-yield agent 10ml, diluting with water by 50 ~ 70 times, or spraying with trimer diphosphate.