When growing tomatoes in greenhouses, watering is one of the most important agronomic measures. It is on whether you water vegetable plants correctly that their good growth and good harvest depend. On the basis of observations, gardeners developed a number of recommendations on how and when it is best to water the tomatoes in the greenhouse, and what level of humidity is necessary for their normal growth. In the article we share them with you.
Features microclimate greenhouses
Before delving into the nuances of watering tomatoes, we suggest to deal with the microclimatic features of greenhouses. 
In summer, in normal weather, the humidity in the greenhouse ranges from 60 to 80%. If the weather is dry and too hot for a long time, then the mark on the hygrometer can drop to 40%. If the heat alternates with rains, then this figure can go up to 90%.
Did you know? The world's largest tomato was a 3.8-pound vegetable grown in Minnesota by Dan McCoy in 2014. The owner of a giant vegetable even gave him a name - Big Zak. Prior to this record was considered a 3.5-pound vegetable grown in Oklahoma, a farmer Gordon Graham.These figures tell us that we should water the tomatoes with caution, strictly following the recommendations and observing the external environmental conditions. With improper watering, the humidity increases and can easily skip the required indicators.
Tomatoes are demanding of moisture, but they do not accept strong humidity. The aboveground part of the vegetable culture develops better in dry air. 
For some reason, there is such a common opinion that the roots of tomatoes also need a lot of moisture. However, it is erroneous. It is important not to overdo it with watering, and not to leave plants for long without life-giving moisture.
Overabundance of water is likely to affect the roots - they will rot. The lack of moisture will lead to poor development of the crop, small fruits, drying of the foliage and even death of the plants from overheating.
Important! Inspect your plants more often. Twisting the leaves along the central vein is a sure sign that the bushes lack moisture. Strengthen watering to avoid negative consequences.
Basics of high-quality irrigation of tomatoes
High-quality watering of tomatoes will depend on:
- watering frequency;
- strict adherence to recommended standards for maintaining soil moisture and air;
- compliance with the required frequency of irrigation;
- following the recommended volume of water applied to each bush;
- choosing the right method and time of making moisture;
- watering water recommended temperature.
The norms of soil moisture and air for tomatoes
For normal growth of vegetable culture, it is necessary that after wetting the soil moisture reaches 90%, and the air humidity reaches 50-60%. Creating such conditions, it is possible to ensure the proper development of the plant and its protection from the development of fungal infections.
To achieve such conditions, it is necessary to know how often it is recommended to water the tomatoes in the greenhouse.
Check out such varieties of tomatoes as "Korneevsky pink", "Blagovest", "Abakansky pink", "Pink Unikum", "Labrador", "Eagle heart", "Fig", "Yamal", "Gina", "Little Red Riding Hood" "," White filling "," Golden Heart "," Samara "," Pink Honey "," Liana "," De Barao "," Persimmon "," Cardinal "," Budenovka "," Dubrava "," Black Prince " , "Bobkat", "Madeira", "Gigolo", "Alsou".Experienced gardeners have noticed that both waterlogging and water shortage have a bad effect on the future harvest of a vegetable plant, therefore it is advised to organize regular watering of tomatoes no more than once or twice a week.
In this case, under each bush should be poured from four to five liters of water. 
Advice on how many times to water the tomatoes, suitable for growing tomatoes in closed ground as a whole and does not depend on whether it is carried out in a greenhouse made of polycarbonate or from another material.
Important! To determine the humidity in the greenhouse, you should get a hygrometer. To determine the soil moisture there is a simple way: take a clump of earth and squeeze it hard in your hand. If it is easily molded, it can be given some simple form, and it also quickly disintegrates, then the earth is well moistened.Another important recommendation that should be followed is to water the bushes strictly at the root.
Water should not fall on the leaves and shoots - this is fraught with the development of diseases and burns. After all, falling on the droplets, the sun's rays will burn the plant's organs.
Crop dependence of irrigation
If you are interested in the cultivation of tomatoes in the greenhouse, you already understand that a successful harvest depends on the observance of several factors: proper lighting, temperature, the presence of minerals and water. 
It is water that takes part in all processes in the plant. Its presence in a sufficient amount in the cells - at the level of 80-90% - guarantees the normal course of physiological processes, in particular, and the distribution of nutrients to all organs of the vegetable culture.
Such a high rate suggests that the plant should receive water without interruption.
Its lack leads to the fact that the processes of photosynthesis are disturbed, mineral substances are incorrectly distributed and can become not useful, but harmful, having a stronger effect than necessary. The plant stops growing, and the fruits are not tied.
Proper and regular irrigation of tomatoes must be adjusted, as it directly affects the volume and quality of the crop. 
For example, improperly adjusted moisture immediately after planting and in the early stages will inevitably lead to the fact that seedlings will develop poorly, some may not live to fruition at all.
Excessive moistening at this time is fraught with strong growth of the ground part, while the root system will remain underdeveloped and will not cope with the task of feeding the whole plant and building fruits. The plant will weaken, drop flowers or bear small fruits.
Learn more about growing tomatoes in the greenhouse, all about staving, garter, mulching, about the fight against yellowing of leaves.
Yield quality depending on irrigation
Of course, the quality of the harvest also directly depends on the degree and regularity of wetting the vegetable in the process of growth and development.
The lack of moisture leads to poor fruiting, as well as the formation of small fruits. The excess and abundance of moisture during the fruiting period provoke the cracking of ripe fruits. 
Watering tomatoes in the greenhouse, depending on the phase of plant growth
Above, we looked at how to water the tomatoes in the greenhouse. In this section, we suggest that you familiarize yourself with the recommendations on the mode of application of moisture, depending on the stage of plant development.
If you look at the amount of water that is contained in the cells of young bushes, it will be 92-95%. Fruiting plants contain from 85 to 90% water. Thus, the replenishment of moisture will increasingly require young planting.
During ripening, watering will need to be reduced. We propose to consider in more detail the norms of how to water the tomatoes in the greenhouse, depending on the phase of their development. 
When planting seedlings
After planting seedlings in closed ground, she will need frequent, but not abundant moisture. At this time, young bushes are still poorly developed root system, and the plant itself is in a depressed state after changing the place and conditions of growth.
A sufficient supply of moisture during this period is the main condition for the adaptation of young tomatoes and the development of their root system.
It should be remembered that poorly developed roots are still not able to absorb large amounts of water, so it is better to water them more often: daily, but in small doses, 2-3 liters per bush.
The basic rule at this time is the regular entry of moisture and the elimination of its stagnation in the upper layer of the soil. 
Active plant growth
After the stem has adapted well to the soil and has begun to grow actively, the irrigation regime will need to be changed. At this time, the above-ground organs of the vegetable culture grow intensively, new shoots appear. Therefore, moisture should be enough to feed them.
From this point on, it is necessary to switch to not too frequent watering - once or twice a week (preferably no more than once every five days), but abundant. The fact that the plants need to be watered will be indicated by the drying of the top layer of soil by 3-5 cm.
If you leave the previous mode, then frequent moistening will lead to the fact that the plants will form a surface root system that can not feed all the green mass and fruits. 
In the period of fruit set
Watering tomatoes during the flowering and fruit set in the greenhouse is very important. Since both an overabundance and lack of moisture at this moment can provoke a fall of flowers and poor formation of the ovary.
At this time, you can adhere to the regime: once every seven days and consumption; 10 liters per 1 square. m or 5 liters per bush.
You will also be interested to know about the cultivation of tomatoes in the open field, according to the Maslov method, in hydroponics, according to the Terekhins method.It is important to ensure that the soil surface is not steadily wet. If there is such a problem, then the number of waterings should be reduced to three times in two weeks. The volume of water while not necessary to cut.
When ripe tomatoes
From the beginning of the reddening of the fruit, tomatoes will no longer need moisture as they used to. 
If you do not change the mode of irrigation at this time, it is fraught with the fact that the fruits accumulate an excessive amount of moisture, and they lose their taste and aromatic qualities.
Therefore, the frequency of proper irrigation of tomatoes during fruiting in the greenhouse - once in 8-10 days. Volume - 10-12 liters per 1 square. m., depending on the state of the plants.
Important! Remove excess moisture from the soil by ventilating the greenhouse. It is important to ensure that plants are not affected by drafts..In late July, watering tomatoes in the greenhouse will need to be reduced. At this time, as a rule, fruit picking has already passed on the lower branches. Carrying out the removal - removal of the apex, which provokes a halt in the growth of bushes.
The upper fruits in July-August are at the stage of final maturation. And most of the leaves on the bushes have already fallen. In this period, the amount of moisture applied to be reduced to 8 liters per 1 square. m 
It is important when watering tomatoes in August in the greenhouse not to overwet them, otherwise the fruit will be watery, cracked, tasteless and unsuitable for transportation.
The ripening of most fruits in the upper part of the bushes is the time when watering tomatoes in the greenhouse should be stopped.
Types of watering organization
Watering tomatoes in the greenhouse can be in several ways:
- Manual - using a watering can, bucket, hose;
- Drip - using a drip system, plastic bottles;
- Automatically.
Manual
When choosing a method of soil moistening, one should remember that tomatoes need only watering at the root, water should not fall on the above-ground part. Therefore, when using a watering can for irrigation, the sprayer should be removed from it. 
This method is ancient, but not very convenient, especially for the elderly, as it is associated with weight lifting. Nevertheless, with the help of this method it is good to control the volume of water that pours out under each bush.
Also, the volume of water is well controlled when irrigating with a bucket. The bucket should be comfortable and fit the required dosage. This method is also associated with considerable physical exertion and is fraught with the appearance of a crust on the soil surface. Soil with this watering must be mulched.
Hosing is good for large areas. This is the most common method used by summer residents.
However, he also has a number of disadvantages:
- the inability to control the amount of water applied;
- the likelihood of damage to landings during its dragging from bush to bush;
- the inability to water with warm water;
- formation after watering the crust on the surface of the soil.
It is important to remember that when using a hose the method of sprinkling for tomatoes is strictly prohibited.Drip
The best way for tomatoes is drip. The budget version of its organization - with the help of plastic bottles. At these tanks the bottom is cut off, and two to four holes with a diameter of 1-2 mm are made in the covers.
Learn also about watering onions, cucumbers, carrots, garlic, cabbage, peppers.Necks dig into the soil at a distance of 15-20 cm from the bush to a depth of 10-15 cm, at an angle of 30-40 degrees. After pouring water into the bottle, it is evenly and in necessary quantities, the plant goes directly to the root system.
The advantages of this method:
- less water consumption than when moistened with a hose, a bucket or a watering can, since water flows directly to the roots;
- air humidity does not rise, since water immediately goes under the soil;
- reducing the risk of fungal diseases in vegetables;
- simplicity in performance and accessibility.
Drip irrigation is also carried out using a special system.Important! With this method it is necessary to ensure that the water from the bottle did not immediately go to the ground. The emptying of the tank should be gradual. Regulation of water intake can be done by reducing / increasing the number and diameter of holes in the lid.Among the advantages of using such a system, besides the direct supply of moisture to the root system, are the following:
- economical water consumption;
- yield increase;
- prevention of soil salinization and leaching of nutrients from it;
- small time and labor costs;
- possibility of watering at any time.
Auto
Automatic irrigation is expensive and, as a rule, used in the industrial cultivation of tomatoes. However, for owners of polycarbonate greenhouses - this is also a great way to establish automated watering throughout the growing season in tomatoes and their fruiting.
Automated systems can irrigate several types: sprinkling, drip, subsurface. The first is not suitable for tomatoes. Systems can be purchased as a finished product, and make his own.
The advantages of automatic irrigation:
- one hundred percent moisture to the roots;
- reducing the risk of disease in plants;
- availability of a programmable timer that regulates the time of water supply and its volume;
- uninterrupted water supply;
- uniform distribution of moisture;
- autonomy of the system allows the use of water of the desired temperature;
- minimum cost of manual labor.
Favorable time of day for watering
With regard to the recommended time for watering, then water the tomatoes in the greenhouse to early morning or evening. At this time of day, the sun will not be able to create a greenhouse effect, and water will be completely absorbed by the roots, and not evaporate, causing an increase in humidity.
If possible, then give preference to morning watering, an hour or two after sunrise. Evening watering, especially at a later time, is fraught with the development of diseases. In addition, the peak of moisture consumption by plants occurs in the period from noon to two in the afternoon.
Did you know? For the first time, tomatoes began to be cultivated by the ancient Aztecs in the 8th century BC. On the gardens of Europe, this vegetable plant fell in the eighteenth century.If evening irrigation is unavoidable, they should be made two to three hours before sunset.
Excessive moisture and its lack
Of course, any plant, if it is cared for incorrectly, will signal its owner with changes in appearance. So, the first sign of a lack of moisture is twisting of the leaves along the central vein.
Lack of moisture or excessively moist soil can cause diseases such as blight, Alternaria, Fusarium.In the future, if you do not take action, such leaves will dry out and fall off.
It is important to understand that with a lack of moisture, plants will not tolerate air temperatures of +30 ° C and higher. They will overheat.
When the first signs of a lack of moisture appear, you should not immediately flood the plants abundantly. The establishment of the correct mode of watering should occur gradually. Remember that the main thing is not so much the frequency as the regularity and volume of the applied fluid. 
Если наблюдается усыхание листьев, то одновременно с восстановлением правильного увлажнения, также необходимо позаботиться о внесении дополнительной подкормки.
Переизбыток влаги первым делом скажется на корнях и нижних частях стеблей, они будут подгнивать. If you notice this trend, then the volume and frequency of hydration will need to be reduced.
Too much moisture during fruiting will result in cracked fruits and a reduction in their palatability.
Did you know? Until today, there is no consensus about what a tomato is - a vegetable, berry or fruit. Botanists attribute it to the berries, technological systematisation - to the vegetable. In the European Union, it is customary to attribute it to fruits.But the wrong selection of water temperature will affect the plant development of a serious disease called late blight, which in a week can leave the owner of the greenhouse without a crop.
Recommendations and tips from experienced gardeners
- If the tank with water for irrigation is located directly in the greenhouse, it should be covered with plastic wrap or a lid so as not to create additional evaporation and an unnecessary increase in air humidity.
- When water is slowly absorbed into the soil, the ground under a bush should be pierced with forks in several places.
- After watering in the greenhouse, all the vents and doors need to be opened to establish good air circulation. The key to proper maintenance of greenhouse tomatoes are frequent airing and mandatory airing after watering.
- After irrigation, loosening the soil is not recommended. The best option would be mulching with straw or dry grass.
- The temperature of the water that you need to water the tomatoes: in the warm season - 18-20 degrees, in the cold - 22-24 degrees.
Tomatoes - warm - and moisture-loving plants that can be planted both in the open and in the protected ground. One of the important and basic measures to care for them is regular and abundant watering.The frequency of supply and the abundance of moisture will depend on the variety of tomatoes, the phase of plant development, weather conditions, climatic zone. The quantity and quality of the crop directly depends on the proper moistening.
