Optimum temperature for growing tomatoes
Heat-loving tomatoes require favorable conditions, including a proper microclimate, watering and light. The right temperature for tomatoes becomes one of the fundamental factors in ensuring the yield.
Optimum temperature for growing tomatoes
Features of planting tomatoes
When planting tomato seedlings and seeds in soil, both the ambient air temperature and the heat indicators in the soil itself at the planting depth matter.
Planting tomato seedlings in insufficiently heated soil means condemning the plants to disease.
The optimum temperature for tomatoes is 15 ° C. With readings on the thermometer below 10 ° C, the root system of tomatoes does not grow and rot, respectively, 10 ° C is the minimum permissible temperature.
Recommendations
The film shelters of tomato plantings allow the maximum heating of the soil to the desired thermal regime, if they are closed immediately after planting, especially at night. In emergency cases, when the seedlings need to be transplanted, but there is no time to warm up the soil, the planting time cannot be tolerated, and when planting tomato bushes, a small amount of hot water is poured into each hole. At the initial stage, such watering provides the seedlings with the required day and night temperature, which can be easily maintained by covering the plantings or using artificial heat.
The established temperature regime for tomatoes affects whether the plants will take root, whether they will actively grow, develop and bear fruit in the future.
Before planting tomatoes, you should check the weather forecast. The absence of frost will allow the plant to harden in the soil and survive even in unexpected cold.
To avoid the death of tomato bushes at an insufficiently optimal temperature during planting, they can be rooted at a shallow depth.
Growing temperature
Plants need to be hardened
Heat-loving tomatoes react sharply even to the slightest changes in temperature and frost in the greenhouse and in the open field. The optimum temperature for growing tomatoes is maintained, depending on the stage of development of the vegetable crop:
- from the moment of sowing the seed to the first sprouts of tomatoes, the temperature is maintained at a level of 20 ° C to 25 ° C;
- at the first shoots or after planting seedlings, the heat level in the greenhouse is maintained for at least 4-7 days in the range from 12 ° C to 15 ° C in the daytime and not less than 6 ° C-10 ° C at night;
- in subsequent periods of growing tomatoes, the temperature is maintained at 20 ° C-26 ° C on days with clear weather, 17 ° C-19 ° C on cloudy days and 6 ° C-10 ° C at night.
An increase in the temperature regime of tomatoes to 25 ° C-30 ° C gives a significant impetus to the growth of seedlings, but in order to avoid excessive stretching of tomato stems, the thermal indicators after a few days return to the usual 15 ° C during the day and 10 ° C at night.Heat hardening of plants when changing thermal regimes within the permissible limits strengthens the roots and develops root processes.
Permissible fluctuations
When the temperature drops below 15 ° C at the stage of active growth, tomatoes slow down the absorption of mineral nutrition, which leads to a slowdown in the development of the root system. As a result, the seedlings do not take root well.
Reduction of heat to 10 ° C stops the process of assimilation of mineral complexes by tomatoes completely. Growth stops.
At the stage of flowering of a vegetable crop, a change in the thermal regime to a level below 12 ° C or, conversely, its increase to 30 ° C leads to the death of ovaries and their abscission. Tomato bushes stop blooming. An excessively warm or cold room in the greenhouse makes the plants sterile. Pollen is afraid of low levels and stops maturing. At elevated levels, the absence of pollen is associated with drying out of the plants.
Critical marks
Air temperature below 5 ° C and above 38 ° C is fatal for tomatoes. Some frost-resistant varieties are able to recover from such a temperature drop and withstand even lower temperature limits (up to -2 ° C), but for a short time. In most cases, the subzero air temperature outside is critical for the plant, they cannot withstand it and immediately die.
Instant death of tomato seedlings of a thermophilic variety is caused by a temperature of 1 ° C or -0.5 ° C. It will no longer be possible to save the plants caught in such conditions, especially if they grow in open ground.
Conclusion
What temperature tomatoes can withstand depends on the variety, but each extreme decrease in heat adversely affects the growth and fruiting of a vegetable crop. As a result of such changes, plants stop growing and begin the fruiting process much later. Frost-tolerant tomato varieties withstand a drop of up to 3 ° C without any particular consequences, while thermophilic tomato varieties located close to the surface of the soil immediately feel the stress of a cold snap.