Proper feeding of tomatoes in a greenhouse: How, when and with what?

Stationary greenhouses are simply an indispensable help for summer residents who are engaged in vegetable growing. After all, they not only protect vegetable crops from unfavorable weather conditions, but also allow for an earlier harvest.

Tomatoes, which are a heat-loving crop, are often grown in greenhouses. However, this method in itself does not relieve the summer resident from the need to care for plants. Tomatoes definitely need fertilizing for normal development and growth. The procedure for applying fertilizers for this crop in a greenhouse has its own characteristics.

Rules for feeding tomatoes in a greenhouse

In a greenhouse, as well as in open ground, tomatoes need regular feeding. When applying fertilizers, it is necessary to maintain a balance between organic and mineral substances. If you overdo it with organic matter, the bushes will grow healthy and powerful, but problems will arise with the formation of ovaries.

If there is an excess of mineral fertilizers, the plants will not be able to absorb moisture normally and may die. Tomatoes need nutrients at every stage of growth. The bushes begin to be fed while the seedlings are growing. When transplanting plants into a greenhouse, the holes are filled with ash, humus and compost. This nutrient mixture is used for absolutely all varieties.

In the future, fertilizing should accompany each stage of tomato development, focusing on the appearance of the bushes. Greenhouse tomatoes become vulnerable to diseases precisely because of a lack of essential minerals. It is recommended to use both root and foliar fertilizers.

It is also necessary to take into account that tall, powerful varieties of tomatoes are usually grown in a greenhouse, which are in dire need of all macro- and microelements for normal growth and fruiting, so the soil is depleted very quickly.

Adequate nutrition will help plants resist fungal diseases and extend the fruiting period.

How many times per season should you feed?

Since orderliness when applying fertilizers is very important, there is a special scheme for fertilizing tomatoes. In general, it represents five main stages that are inextricably linked with the stages of tomato development.

When planting in the ground

By the time the tomatoes are planted, the planting site must be prepared and filled with organic and mineral fertilizers. It is impossible to achieve high yields of this crop on poor and depleted lands.

For good survival and further development of tomatoes, the NKP complex - nitrogen-, potassium- and phosphorus-containing fertilizers - must be added to the soil. If you neglect to enrich the soil composition, seedlings will develop slowly, may begin to get sick, and produce low yields.

Two weeks after landing

During this period, young tomato bushes that have already adapted to new conditions need increased nutrition for growth and development. They need a balanced feed containing three main elements: nitrogen, phosphorus and potassium, as well as microelements. Some gardeners fertilize earlier - already 1 - 1.5 weeks after planting.

During the period of growth

During the period of active growth, tomato bushes need fertilizing with nitrogen and phosphorus.

The interaction of these two elements ensures the proper development of tomatoes.

The supply of phosphorus in the required volume stimulates the accelerated development of the root system, and a sufficient amount of nitrogen in the soil helps the bushes gain green mass in a short time.

During flowering

Tomato bushes begin to bloom approximately 1.5 - 2 months after planting seedlings in open ground, and in greenhouse conditions these periods begin a little earlier. Almost all feeding of tomatoes during flowering is aimed at fruit set. In case of deficiency of potassium and phosphorus nutrition, flowers may fall from the bushes without having time to pollinate. As a result, tomato yields will drop sharply. During this period, it is recommended to avoid the application of fertilizers with a high nitrogen content.

During fruit set

At this time, plants especially need potassium and phosphorus, but fertilizers with a high nitrogen content should be abandoned. There are many complex preparations that can be used during this period, but organic supplements remain the safest.

During the fruiting period

The last main feeding of tomatoes is carried out to improve the taste of the fruit and their accelerated ripening. The main necessary elements for fertilizing already fruiting bushes are potassium, boron, manganese, and iodine.

When receiving such nutrition, the pulp of ripened fruits will be fleshy and sweet due to the accumulation of sugars. If you neglect this stage of the scheme, then the taste of the collected fruits may not be clearly expressed. A couple of weeks before harvesting, all fertilizing should be stopped.

How often should you feed tomatoes?

The feeding schedule for tomatoes depends on the needs of the plant at each stage of cultivation. Young bushes need fertilizer with a high nitrogen content. During the formation of buds and fruits, potassium must constantly be supplied to tomatoes.

Chaotic application of fertilizing will cause an imbalance of microelements in the soil, so it is imperative to adhere to the fertilizing schedule.

Experts recommend applying fertilizers according to the following schedule:

• at the landing stage;
• In 2 weeks;
• during a period of active growth;
• during the formation of buds;
• in the flowering phase;
• during the period of ovary formation;
• at the fruiting stage.

The diagram is approximate; in practice, it is adjusted based on the condition of the plants, determined by their appearance. Sometimes it is necessary to carry out extraordinary fertilizing.

Due to the limited volume of soil in the greenhouse, tomatoes are additionally fertilized leaf by leaf. With the greenhouse method of growing tomatoes, the total number of fertilizing is increased to 10, alternating root and foliar fertilizing with each other.

Suitable fertilizers for young seedlings

Stocky, not elongated and not overgrown seedlings are not obtained by themselves. This requires good soil, timely watering according to schedule, a suitable variety and reliable seeds, optimal lighting and proper feeding of tomatoes. It is enough to carry out the latter twice if the seedlings look healthy. Complex organic and mineral formulations are suitable.

Options for mineral supplements:

1. Nitrophoska. Contains the main NPK complex. The main conditions are to follow the instructions and avoid overdose.
2. Agricola. Contains 20% potassium and phosphorus, 13% nitrogen, as well as magnesium and trace elements.

At what time are fertilizing applied?

For root feeding, choose morning or evening. It is better if it is a dry, cloudy day, when there are no scorching rays and high humidity. The prepared solution is scooped up with a ladle and poured into the base of the stem of each bush, being careful not to get on the plants.

Foliar feeding of tomatoes is always carried out only in the morning. Usually the bushes are sprayed, trying to do it before 10 o'clock. By evening, the leaves must be completely dry, otherwise the development of fungal diseases can be provoked. The surface of tomato leaves is fleecy, so it takes quite a long time to dry.

The tomatoes must be watered first, otherwise the fertilizers may burn the roots, and in this case the nutrition will be absorbed smoothly and rationed.

It is better to time foliar feeding in conjunction with preventive treatments against diseases and pests, but you must remember that preparations containing metal oxides are not compatible with any other substances. This rule also applies to copper-containing products.

In the greenhouse in the spring, tomatoes are fertilized only at temperatures above 15°C, otherwise the plants simply will not be able to absorb nutrients.

What are the benefits of foliar feeding, when it is necessary?

As you know, plants are able to absorb nutrients not only through their roots, but can also absorb nutrients through their leaves. In tomatoes this ability is quite well developed.

Foliar feeding, in a sense, acts as an “ambulance” for plants. In this case, the prepared food immediately falls on the leaves, is quickly absorbed, and for this there is no need to wait until the nutrients with water get into the root layer of the soil and are absorbed by the roots of the plant.

Some gardeners believe that spraying the leaves with a fertilizer solution is necessary only during the flowering phase or during the fruiting period. But this is not so, tomatoes grow and develop well when foliar feeding alternates with root feeding throughout the entire growing season.

In addition to the speed of absorption of nutrients, foliar feeding of tomatoes has the following advantages:

• the vegetative part of the plant develops well;
• the immunity of tomatoes to diseases and unfavorable growing conditions increases;
• promote the appearance of more ovaries, which has a positive effect on productivity;
• low fertilizer consumption compared to the root method;
• foliar fertilizing is more cost-effective than root fertilizing, since less fertilizer is consumed;
• this method requires less labor and time compared to root feeding;
• the possibility of using complex fertilizers, as well as organic and folk remedies.

However, this application method also has disadvantages:

• Do not use high-concentration fertilizer solutions, as this can lead to leaf burns;
• For foliar feeding, it is necessary to use water without chlorine.

How to feed tomatoes in a greenhouse

To feed tomatoes, you can use both industrial fertilizers and folk remedies. After all, once upon a time, vegetable gardens were successfully fertilized with independently prepared fertilizers, while obtaining good harvests. Today, gardeners have a wide variety of fertilizers at their disposal that can be used at all stages of the crop’s growing season.

After disembarkation

2 weeks after planting, the tomatoes are fed with a mineral mixture prepared per 5 liters of water:

• 20 g phosphorus;
• 12 g nitrogen;
• 8 g potassium.

Fertilizer consumption - 0.5 l per 1 bush. These can also be ready-made mixtures of microelements. You can use urea, ammonium nitrate, superphosphate, humate, infusion of wood ash or manure for feeding at this stage. Experienced gardeners praise the fertilizer, popularly called “green tea.” It is prepared from 2.5 kg of chopped green grass, 2-3 liters of mullein and 100 g of ash.

See also: How to fertilize sweet peppers? Two fertilizers that will ensure the harvest

All components are placed in a 25-liter barrel, which is half filled with water and allowed to brew for 5 days. Before use, the composition is diluted in half with water and used for root feeding.

When preparing green fertilizer, it is better to place the container away from the house and cover it with a lid. During the fermentation process, the composition emits a strong and unpleasant odor.

2 weeks after fertilizing at this stage, the tomatoes are fertilized again to support their growth. From ready-made complexes, the “Master” fertilizer is used at this stage.

During flowering

During the flowering period, tomatoes have an increased need for potassium and phosphorus. Large amounts of these elements are present in wood ash. In addition, you can use complex mineral fertilizers.

You can prepare the following mixture per 5 liters of water:

• 1 glass of bird droppings;
• 1 cup mullein;
• 0.5 tbsp. l. potassium sulfate.

You can add 5 g of boric acid and 10-12 drops of iodine to the resulting solution. Boric acid attracts insects for pollination; the window in the greenhouse should be kept slightly open. Boron also prevents the premature fall of buds.

You can additionally feed the tomatoes with yeast. The fertilizer is prepared from 1 packet of dry yeast, 2 tbsp. l. sugar and 3 liters of warm water. When the mixture begins to ferment, the volume of liquid is adjusted to 10 liters. For each tomato bush, it is enough to apply 0.5 liters of this fertilizer. The drug “Ovary”, a solution of which is sprayed on tomatoes during flowering, has worked well.

Tomatoes do not like fresh manure. Before use, it must be fermented by diluting it in half with water and letting it brew for a week. Before use, the fertilizer is diluted in a ratio of 1:10.

During fruiting

Fertilizing applied during the fruiting period can significantly affect the taste of tomatoes and the consistency of the pulp, improving their performance.

You can prepare a nutrient mixture yourself, taking the components in the correct proportions, based on a volume of water equal to 5 liters:

• 1 tbsp. l. superphosphate;
• 0.5 tbsp. l. sodium humate;
• 10 g potassium sulfate.

Fertilizer is applied in an amount of 1 liter per bush. The dose can be increased in case of soil depletion, weakness of the plants themselves, or a small number of ovaries. To increase the number of fruits and improve their quality, you can use the red or brown Kristalon fertilizer.

The use of "Humate" for feeding tomatoes allows you to increase productivity by 60% compared to usual.

The best fertilizers for tomatoes

Many gardeners note the following fertilizers as indispensable assistants in growing tomatoes.

Borofoska

This product is used in rainy weather, when nutrients are washed out of the soil, on sandy soils, and also if crops that absorb large amounts of phosphorus and potassium were previously grown at the site where tomatoes were planted. Allowed to be used as a top dressing throughout the summer. Allows tomatoes to replenish the deficiency of potassium, magnesium and phosphorus. The benefits are obvious: the yield increases by 20%, the fruits become larger, and flowering lasts longer. At the same time, the soil retains a supply of nutrients for the next season.

Borofoska (used specifically for tomatoes) is the most common fertilizer among gardeners.

Ammofoska

A universal fertilizer that can be used everywhere. It contains nitrogen, phosphorus, potassium and sulfur. It is especially necessary to apply it on sandy, clay and marshy soils.

Organic fertilizers can also be used together with ammophoska, which will only improve the results.

Ammofoska as a fertilizer (use for tomatoes, peppers and cabbage) is justified at different times. So, when the question arises of how to fertilize tomatoes when planting in the ground, you can safely answer, Ammophoska. It helps plants better tolerate transplantation. Since it contains potassium, it can be safely applied during the periods of flowering and fruit set, because it is at this time that tomatoes need potassium fertilizers.

Fertika

For infertile soils you can buy Fertika. This is a relatively young drug that is produced in the Russian Federation, but Finnish raw materials are used. The product is available in small pale red granules and in the form of a concentrated solution. Fertik is dissolved in the required volume of water, according to the instructions, and fertilized at the root. You can also apply it in the fall.

Zircon

The preparation Zircon is very important when growing tomatoes. But it is not only a root former, which is why it is used as a fertilizer for tomatoes when transplanting, but also increases resistance to diseases and is a growth regulator. Good for seed germination.

Baby

The drug Malyshok is recommended to fertilize the soil for both seedlings and mature plants. It contains all the elements necessary for good growth of nightshades. Its use has a positive effect on plant growth and root formation, rapid fruiting and helps tomatoes adapt to stressful conditions.

Baikal

You should not lose sight of biofertilizers, one of which is Baikal. In practice, it has been proven that when growing tomatoes using this drug, you can get a rich harvest (from one bush up to 150 kg).

To achieve such success on your site, you need to act strictly according to the following scheme:

1. A container without a bottom for planting tomatoes with a volume of about 1 m² is made from a barrel or boards.
2. Holes are drilled around the perimeter of the container for oxygen access.
3. A 10-centimeter layer of urgasy is laid out at the very bottom.
4. On it is the same layer of soil mixture, which consists of turf, Baikal biofertilizer, ordinary soil and EM compost, taken in equal proportions.
5. At the beginning of May, 1 tomato seedling is planted under a film cover in a prepared container.
6. The lower leaves are torn off and after drying, another 10-centimeter layer of soil mixture is added.
7. This procedure is carried out as the plants grow until the container is completely filled.

What does growing tomatoes this way give a gardener:

• the bushes will have a very powerful root system;
• such a plant does not need to pick off the stepsons, so a real giant grows - a whole tomato tree;
• The first harvest will be a little late, not earlier than mid-July, but fruiting will last for a long time (until mid-October), since such bushes are resistant to cold weather.

Extraordinary feeding

Sometimes tomatoes signal a deficiency of some element by characteristic changes in appearance.

By looking closely at the plants, you can understand what fertilizers they need:

1. With a lack of nitrogen, growth slows or stops. The lower leaves begin to turn yellow, and the upper young leaves become faded in color. To correct the situation, tomatoes are fed with urea, using 25-30 g of the substance per 10 liters of water or a solution of ammonium nitrate prepared in the same proportion. However, it must be remembered that excess nitrogen fertilizers lead to the accumulation of nitrates in fruits.
2. Phosphorus deficiency is manifested by the fact that the underside of the leaves acquires a bluish tint. A solution of superphosphate (30 g per 10 liters of water) will help fill the deficiency of the element. Yes, the preparation of the composition uses boiling water, the fertilizer should infuse for 10-12 hours. For young bushes, apply 0.5 liters of solution; for adult specimens, the dose of fertilizer is doubled. Tomatoes that receive enough phosphorus are less susceptible to diseases.
3. Potassium deficiency manifests itself by curling of the upper leaves and the appearance of a brown border on them. In this case, the tomatoes are sprayed with potassium sulphide at the rate of 15 g of the substance per 10 liters of water. If there is a deficiency of potassium, the root system of tomatoes will be weak, and the fruits will not be large enough.
4. Lack of iron is expressed by the appearance of chlorosis. The main tissue of the leaf blades turns pale, bright green veins stand out against its background. Iron chelate will help eliminate the deficiency of the element. A solution is prepared from 5 g of the drug per 5 liters of water.
5. A lack of calcium is indicated by the fact that the shoots grow thin and overly elongated. Plants can be saturated with this element using calcium nitrate. Consumption - 30 g of the drug per 10 liters of water.

If you apply foliar fertilizing, the results will be noticeable faster. The concentration of fertilizers when sprayed on the leaf is halved.

Effective fertilizing during flowering

It is better to feed plants during intensive flowering. The choice of fertilizers depends on your goals and capabilities. There are 3 options:

1. Mineral supplements. The main advantage is ease of use. Disadvantage: harm if instructions for use are not followed. Simple and double superphosphate, potassium salt, sulfate or potassium chloride will give the desired effect.
2. Organic. The main advantage is environmental friendliness. Used for plant development and disease control. The most popular additives: humates, boric acid and yeast.
3. Complex liquid fertilizers for tomatoes (mineral, organic). The most popular compositions: “Kemira Lux”, “Universal”, “Mortar”, “Senior Tomato”.

What to feed to make them plump

Why do gardeners hope that as they grow, tomato bushes will become strong and plump? Yes, because such plants give a more generous harvest. Thick stems provide adequate nutrition to the fruits and do not break off under the weight of ripe vegetables. The aspirations of gardeners are not always justified in themselves. Tomatoes often need to be helped by feeding.

See also: How to properly care for tomatoes in open ground after planting

If you also encounter this problem, try one of the recipes below:

1. You need to mix 500 g of chicken manure, 500 g of wood ash, 1 glass of sugar, 10 g of dry yeast and pour the ingredients into 10 liters of water. Before use, the mixture must be properly fermented.
2. Tomatoes must be fed in a timely manner to avoid thinning of the stems. The bushes will be strong if they are fed with calcium nitrate or urea in the early stages of growth, using 30 grams of fertilizer per 10 liters of water.
3. You can give tomatoes a large dose of potassium using banana peel tincture. The peels of 4 bananas are placed in a three-liter jar and filled with warm water. The fertilizer should infuse for 3 days in a dark, cool place. After this period, fertilizing is used for watering at the root to strengthen the stems.

It is necessary to monitor the condition of the plants even at the seedling stage, because it is at this time that the tomatoes begin to stretch. In addition to self-prepared fertilizers, you can use industrial preparations, for example, “Athlete” or “Stop Growth”. Both products promote enhanced root growth while simultaneously stopping the growth of the vegetative part.

The growth stimulator “Etamon” has proven itself well when growing tomato seedlings. After using it, the bushes become lush, beautiful, strong, and develop roots well.

To prevent seedlings from stretching out due to a lack of important microelements, they are fed 2 weeks after picking with one of the complex mineral fertilizers:

• "Agricola";
• "Baby";
• "Strong";
• "Emerald";
• "Fertika Lux";
• "Ideal";
• "Solution";
• "Ferovit".

After another 2 weeks, fertilizing is repeated.

If you did everything correctly at this stage, then by the time you transplant them into the ground, the tomato bushes will be strong and healthy, with thick stems and emerald leaves.

How to water tomatoes correctly

Although tomatoes have long been familiar to most summer residents, we should not forget that this crop has its own character and preferences. For abundant fruiting, it is important to take these features into account and follow some rules for watering tomatoes.

Rules for watering tomatoes

• Watering frequency . After the seedlings are moved to the greenhouse, they are watered abundantly. Next time, the soil is moistened no earlier than after 2-3 days, although you can wait longer, depending on the weather. Next, the soil around the seedlings is moistened abundantly 1-2 times a week, taking into account weather conditions, characteristics of the variety and the size of the bush.
• Water volume . Typically, mature tall varieties of tomatoes require about 10 liters of water for each bush, while compact varieties and young plants need 2-3 liters of water.
• Do not water tomatoes with cold water . For watering, it is advisable to use rainwater that has settled and heated in the sun, or even better, water the plants with warm water from the home water supply.
• Watering should be done at the root . Tomatoes do not like to be completely irrigated with water, so under no circumstances should moisture be allowed to enter and remain on the leaves. You can pour water into the furrows, water under the roots from a watering can without a strainer, or use the underground or drip irrigation method.

Beautiful tomatoes on a branch

The optimal time for watering tomatoes is early morning (about 6-7 am); watering later is not recommended.

After the moisture is absorbed, the soil around the bushes is loosened shallowly. Some experienced summer residents advise watering tomatoes once every 5-7 days , even if it is very hot outside. But when adjusting the watering regime for the cultivated variety, it is important to choose the “golden mean” and monitor the condition of the plants themselves.

Important! If the leaves begin to droop, you should immediately water the plants, otherwise you may lose the important first flower clusters and lose part of the harvest.

A ripe tomato has a rich red color

How to carry out the procedure correctly, what not to do

Foliar feeding is no less important for tomatoes than watering. To perform this, nutrient solutions are used that are sprayed onto the leaves of plants.

Carrying out foliar feeding is justified in the following cases:

• if the soil composition is acidic;
• in the case when tomatoes grow on soils that are heavy in mechanical composition and have poor water permeability;
• plants are experiencing an acute deficiency of certain nutrients;
• at the beginning of the budding phase and during flowering;
• if, when transplanting tomato seedlings, their root system was damaged;
• when initial symptoms of tomato disease appear;
• at high soil moisture.

Foliar feeding of tomatoes is carried out by spraying. To complete the work, it is necessary to prepare the necessary tools, a sprayer of any type, a container for diluting the drug with water and fertilizing substances.

Then we perform actions according to the following algorithm:

• Based on the appearance of the tomatoes, taking into account the phase of their development, we determine how and with what we will feed the plants;
• We carry out the work of preparing a nutrient solution for feeding, if necessary we infuse it;
• We process tomatoes in the early morning and late evening, as well as on a cloudy day, in order to minimize the evaporation of the applied product from the leaves and stems;
• When spraying, we ensure that all tomato leaves are moistened with the preparation on both sides.

Attention!
Refrain from foliar feeding tomatoes on a hot or windy day, or during rain. In the first case, a significant part of the drug will evaporate and will not enter the plant, and in the second case, precipitation will wash away the nutrients from the leaves. There is an opinion among experienced gardeners that during the growing season of tomatoes they should do at least 3 foliar feedings in the following phases of plant development:

• in the phase of 2 true leaves of tomato seedlings;
• during flowering;
• during the period of mass fruiting in the second half of summer.

In principle, the use of foliar feeding on tomatoes is not limited in any way; they can be performed every 10 days during the entire growing season, alternating with root feeding.

Important! Never exceed the concentration of the working solution for foliar fertilizing - this will lead to leaf burns.

The use of folk remedies for fertilizing

You can nourish tomatoes with the necessary elements using folk remedies. Gardeners prefer them because they are completely safe and easy to use. The most popular are foliar feeding of tomatoes with nutrient solutions using ash, garlic, whey and herbal infusions.

Wood ash based solution

Wood ash contains a lot of potassium, magnesium and other nutrients. The nutrient solution is prepared according to the following algorithm:

• take 100 g of wood ash;
• fill the material with 10 liters of water;
• leave for 24 hours;
• strain the composition.

After these manipulations, the solution is ready for use. Spraying with this composition is best done during the flowering phase of tomatoes.

Important! Ash foliar feeding of tomatoes is especially effective after a long period of cold weather or a series of rains.

It has been established that ash spraying of tomatoes repels aphids and thrips, and also increases the crop's resistance to powdery mildew.

Whey solution

Whey from sour milk, in addition to containing nutrients, contains beneficial microflora that protect tomatoes from fungal diseases. After processing, a film remains on the leaves, which is a barrier to pathogens.

To prepare a whey-based nutrient solution, follow these steps:

• take 3 liters of whey;
• dilute the product with the same amount of water;
• mix the composition thoroughly;
• strain.

For preventive purposes, it is recommended to spray tomatoes with this composition against late blight three times a month, every 10 days.

Milk solution with iodine

For spraying on leaves, you can use the following composition of ingredients:

• fresh milk – 4 l;
• clean water – 4 l;
• iodine – 15 drops.

This fertilizer composition will provide tomatoes with protection from harmful microflora.

Garlic processing

This treatment saturates the tomatoes with phosphorus, nitrogen and potassium, and also protects the plantings from late blight.

To prepare the working solution, do the following:

• take 100 g of garlic bulbs or leaves;
• grind the product to small components;
• the resulting mass is poured with 200 ml of water;
• infuse the mixture for 24 hours;
• filter;
• the resulting infusion is diluted in 10 liters of water and 1 g of potassium permanganate is added.

Spraying during the flowering phase can be carried out every 10 days. Instead of garlic, you can use infusions of nettle, sow thistle or dandelion.

When carrying out foliar feeding, the specified proportions must be observed to avoid harm to the tomatoes.