What temperature range can tomato seedlings withstand?

Tomatoes are southern plants, but residents of the northern regions also want to taste delicious vegetables from their garden. Many southern fruits can be grown in the greenhouse, it is important to know what temperature the tomato seedlings withstand, so as not to create extreme conditions for the plants. Each gardener plants edible crops for harvest, and not for experiments in what conditions his pets will survive or die.

Even before purchasing seeds, think about where you can create one or another temperature regime for the plantings so that at the last moment you do not rush around the apartment in search of a warm or cool corner. If it is not possible to create comfortable conditions for tomato seedlings, decide: do you need to risk that all work will be wasted, or is it better to plant seedlings purchased on the market in a greenhouse.

Seedlings on the windowsill

Tomatoes are guests from southern countries, they are very demanding on temperature conditions. To understand what tomatoes expect from us, you need to divide the entire period of growing seedlings into several stages:

1. Pecking seeds.
2. The emergence of seedlings.
3. Formation of developed cotyledonous leaves.
4. The appearance of real sheets.
5. Preparation for planting in open ground.

When sowing seeds, it is necessary that shoots appear from them sooner. Wrap the seeds in a damp cloth and place in a warm place with a temperature of about + 22⁰ for pecking. As soon as the grains begin to open, place them in the ground and remove the seedlings in a cool corner with a temperature of + 12⁰ to + 15⁰, where tomato sprouts will develop faster. When you see green loops above the ground, gradually create more and more warm conditions up to + 25 и, and leave this mode until the cotyledons develop.

When too young tomato seedlings begin to grow actively, you need to slow down their development a little. Move the cassettes again to a cool place around + 15⁰. At night, you can lower the temperature by a couple of degrees: such conditions stimulate the formation of flower ovaries and retard the growth of unnecessary lower leaves. When real leaves appear, the daytime temperature needs to be raised to + 20. Night coolness can be left. With this mode, the seedlings will develop well and will be ready for hardening before starting life in a greenhouse or in the open field.

Half a month before you plant the tomatoes in a permanent place, take the plants out during the day on an open veranda or loggia, it should get used to a temperature of about + 15⁰. The first time the seedlings can "walk" no more than an hour in calm, sunny weather, then gradually increase the time the seedlings are in the fresh air. During the last days, plants can be left outside and at night, if the minimum temperature is not lower than + 10⁰. If the seedlings live in a greenhouse, do not forget to open the vents in warm weather, hardening will not harm these plants either.

Development of tomatoes under cover

Do not think that tomatoes live in a greenhouse very sweetly. It is good if the owners are constantly nearby and can open and close the windows and doors several times a day. A gardener can come to a summer cottage 1-2 times a week, during which time the temperature sometimes reaches critically high values ​​during the day, or at night with an open window the bushes can freeze. Cover the planting with non-woven material, it will slightly save tomatoes from temperature extremes.

The most dangerous transitions from heat to cold are under the film with a small greenhouse volume.It is better to spend money once, make a large glazed building, and grow excellent harvests of tomatoes in it for several years, than to change the cover every year, and rush to the dacha to save the planting at every unfavorable weather forecast. A commercial vegetable grower can install automatic vents in the greenhouse, which open or close themselves according to the specified parameters. Set them to low + 18⁰ and high + 25⁰, and your pets will always have the optimal air temperature.

The tomato bush itself has difficulty, but it can live at temperatures up to + 40, but as a result you will only get greens and yellow flowers. They can be picked and put in a vase, since above + 35⁰ the pollen does not ripen, and you still will not wait for the fruit. If, upon arriving at the dacha, you see that the air in the greenhouse is too hot, urgently open the vents and doors, arrange a draft. This procedure, combined with abundant watering, will help cool the plants by about 9⁰.

Tomatoes are not afraid of drafts, it is even useful for them when the breeze dries and freshens the air. In high humidity, pollen cannot break away from the stamen and fertilize the pistil. It is also necessary to open the vents in the greenhouse so that the bees can get into the room and pollinate the tomatoes.

Landing in open ground

Different varieties of tomato can survive at different temperatures, but the overall survival range of tomatoes is taken from 0⁰ to + 43⁰. There are frost-resistant tomatoes that do not die in frosts down to -4⁰, but only in calm weather and for a very short time. If the nights are frosty, planting them outside without shelter is useless. What factors increase the resistance of plants to cold?

• Regionalized varieties,
• low bushes with a strong thick stem,
• well-developed root system,
• adequate nutrition and correct watering,
• absence of diseases and pests,
• hardening.

If you want to grow tomatoes without seedlings, immediately sowing seeds in open ground, do not rush to plant grains. It is important not only to wait for warm days and the absence of frost, it is also necessary that the soil is warm. A covering material or film spread on the ground will help speed up this process. At a soil temperature below + 10⁰, the seeds will not germinate or will lie in the soil for too long and will give rise to weak sparse growth, which often gets sick and dies. To get friendly shoots, you need land warmed up to + 16⁰.

Council. If you want to grow tomatoes without shelter in areas with cool, short summers, choose short, early maturing varieties that develop a powerful root system.

The heat requirements for seedlings growing from seeds directly in the garden are the same as for seedlings at home or in a greenhouse. Until the daytime temperature is about + 23⁰, and the nighttime temperature is not lower than + 15⁰, the seedlings should be sheltered from cold air. Remember that all requirements for warm air and soil apply to water as well. The plant bask in the sun, its roots are tenderly embraced by the loose warm earth, and suddenly the whole idyll is broken by an ice shower from a watering can. Such stress has a detrimental effect on all tomato systems. Do not mock your pets, keep the container of water in the sun, and when the liquid heats up above + 20⁰, water.

Seedlings grown on a windowsill and properly hardened can be planted in open ground if the minimum temperature at night is not lower than + 10⁰. Do not grab your heart in panic when you see + 6⁰ on the thermometer, this is not lethal cold for a tomato, but such coolness is undesirable for good plant development. Keep a close eye on the forecast and cover plantings in time.

Output. Tomato seedlings are a fairly hardy plant, destructive temperatures for it are below 0⁰ and above + 43⁰. Plants do not need to be subjected to such extreme experiments; they can withstand critical values ​​for a very short time. Much depends on the variety and condition of the seedlings.If strong seasoned tomatoes of varieties zoned for the northern area survive a slight frost, then delicate exotic tomatoes, accustomed to heat, will die every last one.

At each stage of development, seedlings need their own optimal air temperature. The seeds should germinate in a cool place, then the seedlings must be transferred to a warmer place, and when the first true leaves appear, the air temperature must be reduced again. Before being planted in a greenhouse or in open ground, it is advisable to harden the tomatoes so that sudden frosts do not destroy them.

Try not to deviate from the recommendations for the optimal temperature for growing tomatoes in the greenhouse, on the windowsill and outdoors. If you keep them hot or cold all the time, the seedlings can survive, but they will weaken, start to hurt. With the wrong thermal regime, the leaves will develop too rapidly to the detriment of the ovaries. When certain values ​​are exceeded, the pollen does not fertilize the pistil, and the flowers die off without producing fruit. Tomatoes will please you with a good harvest only if they themselves live well.