To the question: “At what temperature can you plant tomatoes?” Even the most experienced gardener cannot give a definite answer. The fact is that tomato is a capricious culture and is very thermophilic. To calculate the timing of planting a tomato, you need to take into account a number of factors. Still, it is unlikely that you will be able to achieve an excellent result from the very first time, because growing tomatoes is a process divided into several separate stages, each of which requires an adjustment of all regimes, including the temperature regime.
When it is necessary to plant tomatoes, and on what these terms depend - we will try to understand this article.
Tomato temperature groups
Like any crop, tomatoes have their own growing season, which is directly related to the vegetable variety. That is why, first of all, the gardener should familiarize himself with the recommendations of the tomato seed producer; you can find this information on a bag of seeds.
Of course, the manufacturer’s instructions are very approximate, but thanks to them, one can understand to which temperature group a particular tomato variety belongs. And there are only three such groups:
- The first category includes the most cold-resistant varieties of tomatoes, which, as a rule, are tomatoes with early ripening. These cultures are zoned for the climate of the northern regions, but can be used both in the middle lane and in the south of Russia, if you planted seedlings of such tomatoes before. So, the first group of tomato seedlings is planted in a permanent place, when the night temperature does not fall below 11 degrees, and during the day heat is maintained at 15 degrees. This method of planting is good because the tomato root system can get the maximum amount of moisture left in the ground after winter. By the time this period falls at about the end of April - the first days of May.
- Terms of planting tomato seedlings, belonging to the second temperature group, coincide approximately with the middle of May. By this time, the night temperature should be set at 14-15 degrees in the region, while during the day heat is recommended not lower than 15-20 degrees. The largest part of the tomato seedlings is planted during this period, as it is considered the most favorable: the tomatoes are no longer threatened with frost, and there is still enough moisture in the ground to develop the root system.
- Tomato seedlings planted in the ground after stabilization of the thermometer at a level of 20 degrees, belongs to the third temperature group. Not all tomato varieties are able to develop normally in such conditions, because the roots no longer have enough moisture, and the sun is too hot in the tender leaves of young seedlings. Moreover, late planting threatens tomatoes with various diseases and fungal infections. However, this method is suitable for the latest varieties of tomatoes. And in the northern part of the country, gardeners do not plant tomatoes in the garden before the end of May or even the beginning of June.
Important! All tomato seedlings should be divided into several groups and planted at intervals of 7-10 days.
This significantly increases the chances of getting a good harvest, and this scheme will help determine the most favorable planting dates for a particular tomato variety in a particular region.
The dependence of the timing of planting of tomatoes on the rate of ripening
Everyone knows that tomatoes are early ripening, mid ripening and late. These varieties have characteristic features and, of course, differ in the length of the growing season. The temperature required for tomatoes for normal development may also vary depending on the speed of their ripening.
Here there is such a dependence:
- Late-ripening tomatoes and indeterminate (tall) hybrids of tomatoes are sown on seedlings from February 15 to 25. By the time the plants are transplanted, the seedlings should be about 70-80 days, so the dates of planting it in a greenhouse or in open ground correspond to the first decade of May.
- Varieties of tomato with medium ripening periods and the same hybrids should be sown on seedlings on March 5-10, and transferred to a permanent place around May 10-20.
- Seeds of early ripening varieties, as a rule, are sown from March 15 to 25, seedlings can be taken under shelter in mid-May, and in open ground - no earlier than the first days of June.
Attention! And yet, a lot depends on which part of the country the region is located with the garden plot, because the climate and the average temperature directly depend on this.
It is these indicators that are fundamental in calculating the timing of planting tomatoes.
At what temperature to plant tomatoes
The process of growing tomatoes is divided into several stages:
- preparing tomato seeds for planting;
- planting seeds for seedlings;
- dive tomato seedlings;
- hardening of tomatoes before planting at a permanent place;
- planting seedlings in open ground or in the greenhouse.
But even after all these stages, the temperature of the air and the soil can significantly affect the development of the tomato and their yield. Moreover, the impact may be too low or too high thermometer.
Important! Most tomato varieties react to such critical temperatures: 5 degrees at night and 43 degrees during the day.
It is under these conditions in plants that irreversible processes begin, leading to the rapid death of tomatoes.
Not only the critical marks of the thermometer adversely affect tomatoes. For example, prolonged coolness at 16 degrees during the daytime will result in the following:
- stopping the growth of lateral shoots on the root system of a tomato;
- the inability of the roots to absorb minerals and moisture;
- reducing the number of ovaries and reducing the yield of tomatoes.
Constant heat in the range of 30-33 degrees also ends badly - tomatoes shed leaves and flowers, which leads to zero yields.
The fight against the cold is aimed at covering the plants; therefore, tomatoes are often grown in greenhouses, temporary greenhouses, and cover the seedlings for the night with agrofibre or plastic wrap. It is also possible to prevent overheating of plants: tomatoes pritenyut, the ground around the bushes are mulched to reduce the evaporation of moisture from the soil, often watered bushes.
Seed preparation and planting tomato seedlings
For planting seedlings, you must purchase or collect independently high-quality planting material - tomato seeds. Before planting the seeds are prepared in a certain way, one of the preparation steps is hardening of the planting material: first, the seeds are heated, then placed for several days in the refrigerator.
Proper preparation contributes to seed readiness for harsh climatic conditions; seedlings obtained in this way will be able to withstand fluctuations and temperature fluctuations, it is better acclimatized at a new place.
After the seeds have been sown, the containers are covered with a film and placed in a warm place - they can only germinate when the air temperature stays at 25-27 degrees.Tip! It is recommended to always increase the temperature by a couple of degrees, taking into account the regime indicated on the package with tomato seeds. This contributes to the rapid development of plants and earlier harvest.
In such conditions, it is impossible to keep the seedlings for too long - tomatoes can easily stand and die. Therefore, as soon as the first shoots appear, the film is removed, and the containers with the tomatoes are placed in a cooler, but lighter place. The temperature there is maintained at 20-22 degrees.
At this stage of development, tomato seedlings need alternating night and daytime temperatures, so the thermometer should show a few degrees less at night - the best value is from 16 to 18 degrees.
After the tomato seedlings have been pickered, it is necessary to maintain the same temperature regime and alternate night and daytime temperatures, but at this time it is necessary to begin gradually hardening the seedlings.
Proper hardening of tomato seedlings
Before planting a tomato in a permanent place (in the greenhouse, greenhouse or in the open ground), seedlings must be hardened.Important! Independent cultivation of tomato seedlings has a lot of advantages, one of which can be considered that the owner is confident in the readiness of plants for new conditions.
But, buying tomato seedlings, you can never be sure that it, in general, hardened.
Hardened tomato seedlings are much stronger and more adaptable than usual - these tomatoes will quickly get used to the new external environment, very soon they will start to give new shoots and roots, will form ovaries and will give the crop. The probability that non-quenched plants will be able to take root in a new place is extremely small, this is possible only in a very warm climate and with normal humidity.
Start hardening tomato seedlings as early as possible. Only pickled tomatoes with one or two true leaves can be safely carried out on the balcony or in the yard. But this is possible only in one case: if the air temperature does not fall below 15 degrees.
Spring is rarely so warm that at the end of March and early April, during the day, the thermometer showed more than 10 degrees. Therefore, many gardeners and gardeners use for hardening seedlings the same greenhouses, where tomatoes will later be transplanted. During the day, the air in the greenhouse warms up sufficiently, and you can protect the plants from the cold earth by lifting them up on racks or benches.
When the night frosts pass, and the air will be warm at night (about 8-10 degrees), you can begin the night hardening of tomato seedlings.
However, you should not put pots and boxes with plants directly on the ground, it is better to lift them on window sills or special shelves.
Important! The task of the hardening process is to train a tomato to a gradual decrease in temperature.
Therefore, this procedure should be carried out in several stages: start with a slightly opened window leaf, then carry out the seedlings for a few minutes, then leave the tomatoes outside for the whole day, only after that they switch to night hardening.
Move the tomato seedlings to the greenhouse
Greenhouse is needed in order to accelerate the ripening of tomatoes. After all, seedlings are transferred to protected ground much earlier than to simple beds. Polycarbonate, glass or plastic film let the sun's rays inside the greenhouse, but at the same time do not let the heat out.
Thus, a certain microclimate is created inside the greenhouse, constant temperature and humidity are maintained - all this is very useful for tomato seedlings. In such conditions, the plants develop rapidly, create the ovary and form the fruit.
But, if the air in the greenhouse warms up quickly enough (as early as March, the temperature may be sufficient for growing tomatoes), then the earth becomes not much warmer than that located on simple beds.
To speed up the process of warming the greenhouse, you can use one of the methods:
- Equip ground heating with electricity, warm water, or other volatile systems.
- Raise the beds by 40-50 cm from the ground level, thereby protecting the tomatoes from ground frost.
- Create warm beds, using the natural processes of rotting and fermentation, pouring compost or humus on the bottom of the trench, and planting tomato seedlings on this layer.
When the ground in the greenhouse becomes warm (at 10 degrees), you can safely plant tomatoes.
Do not forget that too hot air is detrimental for tomatoes, to maintain a normal microclimate it is necessary to open the vents, use ventilation or tilt the greenhouse film walls.
Terms of planting tomatoes in the ground
To calculate the correct timing of planting tomatoes in the ground, as mentioned earlier, you need to consider several factors at once. But even after that, there remains a high probability of the return of cold weather, frost or other surprises from the weather.
No one is immune from mistakes, which is why experienced gardeners never plant all their seedlings of tomatoes in one day - this process is stretched by dividing the total number of plants into several parts.
If we talk about a strip with a temperate climate, then the first batch of tomatoes are planted here in late April (April 20 - May 1). The largest part of the plants should be planted in the middle time - May 1-10. And finally, tomato seedlings are planted in the middle of the month (10-20 numbers), trying to protect at least part of the crop from possible frost.
Because of such difficulties in the calculations, it is possible to recommend to summer residents to annually record all the dates when tomatoes are sown for seedlings, diving, transferring to the ground what crop is harvested - this statistic will help determine the most optimal dates for planting tomatoes in a particular locality.
All farmers want one thing - to grow a tomato crop as early as possible and collect a record number of fruits. Haste in this process is not associated with the ambitions of gardeners - the sooner the tomatoes ripen, the less they have a chance to get a fungal infection, suffer from pests, catch a period of intense heat or “live” until the autumn cold.
Today there are lots of ways to prepare the beds, aimed at bringing the tomato seedlings into the ground a little earlier. It can be:
- high beds of wooden planks or other scrap materials;
- planting tomatoes in straw or sawdust;
- use for seedlings individual containers (pots, buckets, boxes, bags);
- warming the land with compost, food waste, humus or other suitable substrates;
- cover of planted tomatoes with film or agrofibre, used only at night or in bad weather.
Rescue seedlings from frost
Despite all the precautions and complex calculations, it is often the case that the frosts catch gardeners off guard. And then it is necessary to take urgent measures to save tomato seedlings in the open field.
There may be several such methods:
- Shelter with a film or agrofibre, lutrasil and other special fabrics. For this method, it is recommended to provide a small metal arch or frame on which you can throw covering material so as not to damage the tomato seedlings.
- Glass jars, plastic containers, or even ordinary buckets can also protect tomatoes from freezing, another thing is that finding dishes in sufficient quantities is not always possible. This method is more suitable for small areas with a couple dozen bushes.
- If frost threatens a large plantation of tomatoes, you can try to heat the plants with smoke. For this you need to kindle a fire from the windward side. As fuel, it is necessary to use what gives a lot of smoke: last year’s foliage, wet thick logs, wood bark, wet sawdust. Smoke will travel along the ground, thereby heating the tomatoes.
- Severe frosts can even threaten tomatoes planted in greenhouses or greenhouses. There, the plants also protect, pouring sawdust on the bushes, straw, or covering them with cardboard boxes, plastic buckets, bottles.
All this helps to ensure that the specific dates of planting a tomato simply do not exist. Each gardener or summer resident must determine the dates of planting empirically, watching his tomatoes for several seasons in a row.
Greenhouses or greenhouses may slightly facilitate the process of growing tomatoes, but such methods have their own characteristics - the increased humidity and the likelihood of overheating due to too high temperatures and insufficient ventilation pose a threat to plants.
Being engaged in tomatoes, the agrarian must understand that it will not be easy - the culture is very capricious and whimsical. But the fresh tomatoes on the table and a good harvest completely pay off all the spent effort and money.