Open-air tomato planting technology

There are many ways to grow tomatoes, both outdoors and not outdoors. So how can we better grow tomatoes outdoors?

1. Quantitative indicators for high-yield cultivation of tomatoes

Tomatoes' temperature requirements: Tomatoes like warmth, and the suitable temperature during the day is 25℃-28℃, and 16℃-18℃ at night. Below 15℃, tomato seed germination, pollination and fertilization, and tomato turning red are affected; below 10℃, growth is slow, reproductive development is inhibited, stems and leaves stop growing at 5℃, 2℃ are cold damage, and 0℃ is frozen to death. Above 35℃, reproductive development is affected, and above 40℃, physiological disorders and heat death. Adequate light and appropriate temperature difference are conducive to nutrient accumulation and ripening, promote healthy plant development, prevent excessive growth, enhance tomato's disease resistance and stress resistance, and increase yield.

Tomato humidity requirements: The basic principle is that except for germination, emergence, and the seedling slowing period after transplanting, high temperature and humidity are required, high humidity is not required in other periods. Regarding water requirements, except for proper water control before transplanting, during the flowering period, and during the ripening period, sufficient water supply should be ensured in other periods.

Principles of tomato nutrition supply: Tomatoes require a large amount of fertilizer, and sufficient nutrition should be guaranteed at all stages. However, the fertilizer requirements at each growth stage are somewhat different. Nitrogen fertilizers are emphasized in the early stage, potassium fertilizers are emphasized in the later stage, and the demand for phosphorus fertilizers is carried out throughout the growth period. However, the demand for potassium fertilizers must be guaranteed during the entire growth period.

Under the condition of ensuring the normal growth and development of tomatoes, low-temperature training of tomatoes can not only improve the plant's own heat and cold resistance, but also reduce the cost of heating and insulation. Generally speaking, the optimal temperature is required at the turning point and key period of tomato growth, such as germination, emergence, flower bud differentiation, pollination and fertilization, and ripening period, as well as after seedling transplanting, to ensure the appropriate temperature to promote normal reproductive physiological processes and to heal and resume growth as soon as possible after injury; and before seedling transplanting and transplanting, sufficient training is required to ensure that the plant safely passes through the difficult period after injury, and the temperature can be slightly lower during the normal growth stage.

The key to tomato cultivation is to cultivate strong seedlings. The indicators of strong seedlings are 6-7 leaves, 60-70 days old, 20-23 cm high, and 60%-70% visible flower buds.

2. Prepare nutrient soil

Prepare the nutrient soil according to a certain proportion, requiring the porosity of the nutrient soil to be about 60%, pH 6-7, containing more than 100 mg/kg of available phosphorus, more than 100 mg/kg of available potassium, and 150 mg/kg of available nitrogen. It should be loose, retain fertilizer and water, and have complete nutrition. Spread the prepared nutrient soil evenly on the sowing bed (10 cm thick) or in the seedling tray.

3. Seed processing

Tomato seed disinfection. There are two methods: (1) soaking seeds in warm water, which means soaking the seeds in clean water for 1-2 hours, then taking out the seeds and putting them in 55 degrees Celsius hot water, maintaining the water temperature uniformly and soaking for 15 minutes, and then continuing to soak the seeds for 3-4 hours. When soaking seeds in warm water, generally one part seeds and two parts water; stir constantly and quickly to heat the seeds evenly to prevent scalding the seeds; third, hot water should be added continuously to maintain the water temperature of 55 degrees Celsius. This can prevent the occurrence of diseases such as leaf mold, ulcer disease, and early blight. (2) Soaking seeds in trisodium phosphate, which means first soaking the seeds in clean water for 3-4 hours, taking out and draining, and then soaking them in 10% trisodium phosphate solution for 20 minutes, taking out and washing. This method has a relatively obvious effect on tomato virus diseases.