Growing tomatoes in a greenhouse

Greenhouse tomatoes appear much earlier than ground ones, and the number of such fruits will be at least twice as large. The technology for growing tomatoes in a greenhouse and in the open field is somewhat different. In order to get a good crop of greenhouse tomatoes, you need to know some of the secrets and features of this process.

What are the rules for growing tomatoes indoors, how to care for greenhouse tomatoes, what fertilizers to feed and how often to water – this article will be about this.

Growing tomatoes in a greenhouse step by step

Having decided to grow tomatoes in a greenhouse, the gardener must know some of the nuances. For example:

• greenhouse tomatoes are more likely to suffer from fungal infections, so disinfection should come first;
• in greenhouses and greenhouses it is necessary to plant only parthenocarpic or self-pollinating varieties that do not need pollinating insects;
• if tomatoes needing pollination were chosen for planting in the greenhouse, you need to start attracting bees to the greenhouse or do manual pollination with a brush, for example;
• it is necessary to constantly monitor the temperature and humidity inside the greenhouse, because tomatoes love such conditions: 23-30 degrees and 60-70% humidity;
• regular ventilation is mandatory, therefore, during the construction of the greenhouse, you should take care of a sufficient number of vents or equip a forced ventilation system;
• growing tall tomatoes in a greenhouse will require supports or rods to which plant stems can be tied;
• planting a tomato in a closed greenhouse should in no case thicken, as this significantly increases the risk of fungal infections and rot on tomatoes.

After the greenhouse is built, you can proceed directly to the cultivation of tomatoes in the greenhouse. This process should consist of several mandatory steps:

1. Buying planting material or growing tomato seedlings on your own.
2. Preparing the soil and the greenhouse itself for planting tomatoes.
3. Transferring tomato seedlings to a greenhouse.
4. Pollination of tomatoes (if necessary).
5. Tying tomatoes on supports and forming bushes.
6. Watering and feeding tomatoes.
7. Harvesting and storage.

Sowing tomato seeds for seedlings

Externally, greenhouse tomatoes are indistinguishable from ground tomatoes: absolutely any variety of tomato can be grown in a greenhouse. But anyway selected and special tomatoes designed specifically for greenhouses. Such varieties have a number of features:

• have immunity to fungal infections;
• do not need pollination;
• love warmth and humidity;
• most greenhouse tomatoes belong to the group of indeterminate varieties, that is, tall;
• have higher productivity.

Having decided on the variety of tomatoes for your greenhouse, you can go for seeds. If tomato seeds enclosed in colored capsules are selected, they will not need additional processing before sowing – the capsule already contains all the substances necessary for normal and rapid development.

Raw seeds will need to be prepared for sowing seedlings:

1. Treat with an antiseptic preparation (for example, soak in a weak solution of potassium permanganate).
2. Sprout by covering with a damp cloth and placing in a warm place.
3. Harden off by putting the germinated tomato seeds in the refrigerator for a couple of days.
4. Soak tomato seeds for several hours in a growth stimulator or in a complex mineral fertilizer.

Now the seeds can be planted in the prepared substrate. The soil for tomato seedlings should be slightly acidic, loose, well retaining moisture and breathable. A mixture of equal parts of such ingredients is suitable: peat, sod land, humus.

In the mixed soil, you can add a liter jar of coarse river sand and the same amount of wood ash. Now the earth needs to be disinfected, for this you can freeze it on the street (if the temperature is below zero) or hold it for about 30 minutes in the oven (you can use the microwave).

A good antiseptic is considered a solution of potassium permanganate – they simply pour over the ground laid in containers. By the way, containers for tomato seedlings should be shallow – about 5-7 cm tall. So, the root system will be able to develop normally.

Drainage from pebbles, bark or gravel is laid at the bottom of each pot or box for tomato seedlings. Substrate is poured on top and rammed a little. Now they make indentations and put germinated prepared tomato seeds in them. Seeds are covered with a thin layer of fine soil and sprayed with warm water from a spray bottle.

Containers with tomato seedlings are covered with glass or film and placed in a very warm place – they will be there until green sprouts appear.

As soon as tomato loops begin to appear from under the ground, the shelter is removed, and the containers with seedlings are placed on the windowsill or in another bright and warm place.

Caring for tomato seedlings

Like regular seedlings, greenhouse tomatoes need to be watered regularly. Do this at first only with a spray gun, when the plants get stronger, you can use a small watering can or mug. Water can wash the roots of plants – this must be remembered.

At the stage of the appearance of two or three true leaves, tomato seedlings dive – transplanted into larger containers. Diving also helps the tomatoes prepare for a future transplant into the ground; at this stage, you can also control the length of the stems and form the root system.

After diving, you can slightly reduce the temperature – it can be 18-23 degrees. It is not worth feeding tomato seedlings, it is better to apply fertilizers already when the tomatoes are transplanted into the greenhouse and go through the process of acclimatization.

Tomatoes in a greenhouse will be healthier if they are taken outside or onto a balcony a couple of weeks before transplanting (you can leave seedlings daily for several hours in the same greenhouse).

Transplanting tomato seedlings in a greenhouse

Tomato seedlings are ready for transplanting into the greenhouse when the stems have reached 18-25 cm in height, the plants have 7-8 true leaves, the first inflorescences begin to appear, but there are no ovaries yet.

Until this moment, the earth in the greenhouse should also warm up – the temperature of the soil at a depth of 10 cm should be at least 12 degrees. If you plant tomatoes in too cold ground, the development of plants will stop, subsequently they may die altogether, or this will affect the yield of tomatoes. On the day of the transplant, the weather should not be too hot, it is good if it is cloudy or rainy outside.

You can speed up the warming of the soil with a black plastic film. They simply cover the ground in the greenhouse with it until they reach the desired temperature. In the most extreme case, you can use hot water to water the holes before planting the tomato.

Before this, the walls and structures of the greenhouse must be thoroughly washed and treated with an antiseptic. It is recommended to use a new soil every year, but you can simply disinfect it.

Fertilizing the land before planting tomato seedlings is mandatory – superphosphate and potash fertilizers are used for this. Peat, humus or rotted sawdust will help loosen the soil, the amount of such additives should be about a bucket per square meter. When everything is ready, make holes for tomato seedlings.

The scheme for planting tomatoes in a greenhouse, of course, depends on the type of plant and variety. So:

• undersized early ripe tomatoes are planted in a greenhouse in two rows, observing the staggered order of the holes. The distance between adjacent tomatoes should be 35-40 cm, between rows leave at least 55 cm.
• Low-growing (determinant) and standard varieties of tomatoes, which are usually grown in one stem, can be planted a little thicker: 30 cm between bushes, rows at a distance of half a meter from each other.
• Indeterminate tomatoes are also planted in a checkerboard pattern. Between rows, an interval of 80 cm is observed, the distance between adjacent bushes should be at least 70 cm.

The most important thing is that the planting of tomatoes does not thicken. If such a trend is observed, it is necessary to deal with the removal of side shoots. But there should not be too much distance between tomato bushes, otherwise the plants will start to fall.

The process of planting a tomato itself is no different from planting seedlings in the ground: about a liter of warm water is poured into the hole, the seedlings are taken out of the pot, the roots are straightened and placed in place, covered with earth and lightly rammed.

Do not plant too deep, as this will lead to the formation of lateral roots, which will slow down the growth of plants. Only overgrown tomatoes can be planted a little deeper, but it is better not to allow this.

Experienced gardeners recommend removing cotyledon leaves before planting tomatoes in a greenhouse. The same is done with yellowed or damaged leaves.

Within 10-12 days after transplanting into the greenhouse, the tomatoes are not touched: at this time they acclimatize, so it is not worth watering or fertilizing the seedlings in the greenhouse yet.

Tying and pinching tomatoes in a greenhouse

Two weeks after planting the seedlings in the greenhouse, you can start tying the stems. Tall tomatoes in a greenhouse need to be tied up unequivocally, usually trellises are used for this, about 180-200 cm high. With low-growing varieties, everything is much simpler – their stems can not be tied up (only when there are too many fruits on the bushes, it is better to install supports anyway).

For tying, use a thread that is not too thin, otherwise the stems of the tomato may be cut. It is better to use bandages or thin strips of cotton fabric for this. The free end of the rope is tied around the bottom of the bush and gently wrapped around the entire stem. As the tomatoes develop, the stems are tied up additionally.

Pasynkovanie – the formation of a bush by breaking off unnecessary shoots. This procedure is also not performed with all varieties of tomatoes, for example, standard tomatoes already give a few lateral processes, the bush itself is compact and not sprawling.

In other cases, it is necessary to regularly remove stepchildren in order to prevent the formation of an excessive number of ovaries – this will deplete the plants and reduce yields.

Form tomato bushes in one, two or three stems. In the case when only one stem is left, it turns out to collect the earliest harvest, but there will be few fruits, because only 4-5 brushes will remain.

Therefore, most often tomatoes are formed in two or three stems – this way the yield will be high, and the fruits will ripen early enough. 7-8 brushes are left on each stem, all other shoots must be removed until their length has reached more than five centimeters.

Pollination of a tomato in a greenhouse

As mentioned above, not all varieties of tomatoes need pollination – for a greenhouse it is better to use tomatoes that do not require the participation of insects. But many gardeners note a more pronounced taste and aroma in varieties that require pollination.

In this case, you will have to seriously tinker with greenhouse tomatoes:

1. One option is to install evidence with bees directly into the greenhouse. This should be done only at the flowering stage of the bushes. But this method is good only for summer residents who are breeding bees.
2. Another method is suitable for those who live near an apiary or have a beekeeper neighbor: you need to attract beneficial insects to the greenhouse. For this purpose, fragrant flowers are planted at the entrance to the greenhouse, in the greenhouse itself you can place small containers with sweet syrup or irrigate tomato bushes with this solution.
3. For some varieties of tomatoes, intensive ventilation of the greenhouse is enough: this is how pollen is transferred from flower to flower by air flow. In the flowering phase in the greenhouse, you need to open all the windows and doors to create a draft. Before this procedure, you need to reduce the humidity in the greenhouse, again, using ventilation and stopping watering. Pollen should be crumbly and dry. But irrigating the bushes with a sprayer will help to fix the result – this will help the pollen to germinate on the pistils of the flowers.
4. The most time-consuming method is to transfer the pollen by hand using a paint brush. This option will suit summer residents who have small greenhouses with several dozen plants.

Watering and feeding tomatoes

Care in the greenhouse consists in feeding and watering tomatoes.

Tomatoes need to be watered rarely, but plentifully – This rule applies to both ground and greenhouse plants. For tomatoes, high humidity is detrimental, especially in a closed greenhouse. This provokes the development of fungal infections, which can lead to the loss of the entire crop.

To prevent such a situation, you should remove the lower leaves, monitor the thickening of the plantings, and regularly ventilate the greenhouse. And most importantly – water the tomatoes only under the root, preventing the stems and leaves from getting wet. Drip irrigation of tomatoes in greenhouses is very effective, therefore, if possible, this system should be installed without fail.

Greenhouse tomatoes should be watered no more than twice a week. The amount of water for each bush varies depending on the phase of plant development: at first, watering should be more abundant, and by the phase of formation of ovaries and ripening of fruits, the amount of water should be gradually reduced. If this is not done, the fruits will crack, and the plants themselves may become ill with late blight or another infection.

For the entire growing season, tomatoes are fed at least three times. The feeding schedule is approximately the following:

1. The first feeding is carried out three weeks after planting the seedlings in the ground. Plants need nitrogen at this stage. Therefore, they take nitroammophoska and liquid mullein, dilute them in water and pour a liter of such a solution under each tomato bush.
2. After another 10 days, the tomatoes need to be fed with a complex mineral fertilizer. The Fertility composition is effective, to which you can add a little potash fertilizer.
3. Two weeks after the second feeding, proceed to the next stage. For this, they take superphosphate, wood ash or sodium humate with nitrophoska. The components are dissolved in water, about five liters of the composition must be poured per square meter.

It is very important not to overdo it with nitrogen fertilizers, because their excess will only lead to an increase in green mass – the yield will not increase from this. To understand what tomatoes lack, one should observe the color of the leaves and the general condition of the plants.

Another of the essential components of care is ventilation. Tomatoes are not afraid of drafts, so you can ventilate the greenhouse in any way. Windows and doors must be opened for at least a couple of hours after each watering. In addition, the greenhouse is ventilated daily in too hot weather, or when the temperature “overboard” rises above 23 degrees. At night in the greenhouse should be about 16-18 degrees Celsius.

Harvest and storage

In a greenhouse, growing a tomato takes 1,5-2 months. During this time, the fruits have time to ripen and turn red. That means it’s time to start harvesting.

Tips for growing and harvesting tomatoes in a greenhouse are:

• in heated greenhouses, fruits can ripen already in spring – in this case, ripe tomatoes are harvested every two to three days. In the summer-autumn period, you will have to harvest daily.
• It is necessary to pluck the fruits so that the stalks remain on the bushes.
• Put the tomatoes in small boxes, in several layers, so that the fruits are not crushed and crushed.
• You can collect both pink and red tomatoes: unripe fruits will just have time to ripen if they are supposed to be transported for a long time.
• If you pick tomatoes unripe, you can increase the yield, because neighboring tomatoes will begin to pour faster and more abundantly.
• Tomatoes folded in several layers are recommended to be interspersed with soft layers of peat, hay or sawdust.
• If you need to keep the fruits for a long time, each tomato should be wrapped with soft paper.
• It is better to harvest in the early morning or wait for the evening.

We summarize

Growing and caring for tomatoes in a greenhouse differ little from cultivating this crop in the open field. To achieve high yields, you will have to follow the rules of tomato farming and have a good understanding of the features of a capricious culture.

Tomatoes grown in a greenhouse can be no worse, if not better, than garden relatives. Excellent taste and a standard smell are always present if the rules of irrigation were followed, the necessary fertilizers were applied, and the flowers were pollinated normally.

A video about growing tomatoes in a greenhouse will help you deal with the remaining subtleties and understand all the nuances of this difficult matter: