Many vegetable growers prefer to grow tomatoes and other crops in the greenhouse - this allows you to get the first crop of fresh fruits early enough. But sometimes on the tomatoes grown in the greenhouse, white spots can form, signaling the presence of a disease or pests. What factors contribute to this, how to deal with tomato diseases and what to do to prevent their occurrence - more on this later in the article.

Features of growing tomatoes in a greenhouse

The process of growing tomatoes in greenhouse conditions is long and time-consuming. But if everything is done correctly, the result will not disappoint, and all efforts will be rewarded with a good harvest.

Important! To collect a good crop of tomatoes, you need to consistently and clearly perform all the steps described.

The sequence of growing tomatoes in a greenhouse is conventionally divided into several stages:

1. Preparation of seeds, land and containers for seedlings.
2. Sowing seeds and their germination in a prepared container.
3. Pick of tomato sprouts after the appearance of 2-3 leaves on them.
4. Planting tomato seedlings in a greenhouse.
5. Care for tomato sprouts in greenhouse conditions: watering, fertilizing, stepsoning, garter.
6. Harvesting.

In order for the plants to grow well and give a lot of ripe fruits, you need to create a microclimate suitable for the plants in the greenhouse and provide them with the necessary care:

1. Optimum air temperature. So that at the time of transplanting the seedlings do not freeze, the greenhouse is covered with a double layer of film. For better thermal insulation between the layers of the film, it is useful to leave a small layer of air. Even in cloudy weather, the temperature inside the greenhouse should be at least +18 ° С, and on a clear and sunny day + 24–26 ° С. At night, the air temperature in the structure should not fall below +15 ° C.
2. Good ventilation - needed to eliminate dampness and is carried out 2 hours after each watering of tomato bushes. For good ventilation, open all available doors and windows of the structure, raise the film to open the bottom and ends of the greenhouse.
3. Soil disinfection and fertilizer - necessary for the normal growth of tomatoes and the prevention of plant diseases. To get rid of last year's soil layer, you need to remove the upper 12 cm of soil. Then the soil is watered with a solution of copper sulfate to eliminate a possible infection and humus is applied as fertilizer. 2 weeks after planting the seedlings in the greenhouse, the soil is treated with phosphorus-potassium preparations. Feeding should be done 3-4 times per season.
4. Suitable planting pattern - It is selected depending on the variety of tomatoes that will be grown in the greenhouse. Low-growing tomato varieties are planted in 2 rows, the distance between which is 55–60 cm. 35–40 cm is left between the plant bushes. If a tall variety of tomatoes is grown in the greenhouse, they are planted in a checkerboard pattern. Between the rows leave a distance of 75–80 cm, and between tomato bushes - 60–70 cm.
5. Timely watering - carried out for the first time only after 1.5 weeks after transplanting tomato bushes into the greenhouse. Tomatoes are poured with warm water every 4 days. During the flowering period of plants per 1 square. m of soil you need to spend about 13 liters of water.

Did you know? The world's largest greenhouse created in the UK. It consists of two interconnected domed structures in which more than 1000 species of plants grow.

6. Stitching and garter of tomato bushes - help plants withstand the weight of tomatoes, are the prevention of certain diseases. Trimming of lateral shoots is carried out in the morning, so that the cut point dries in the sun. A garter of tomatoes is done 3-4 days after planting. In greenhouses, linear and frame trellises are usually used to tie up tomato bushes.

Why did white spots appear in the greenhouse on tomato leaves and what should I do?

Sometimes when growing tomato bushes in greenhouses, white spots appear on the leaves of plants. They can form on young tomato sprouts or on already mature bushes with fruits, but their appearance always indicates the presence of certain problems with the plant. Consider the main diseases of tomatoes, characterized by the appearance of white spots.

Sunburn

Tomatoes need sunlight, without it they cannot grow and bear fruit. But too bright sun rays can cause burns on plants on the upper surface of the leaves.

Symptoms of sunburn include:

• light spots on leaves that were in direct sunlight;
• the tips of the leaves begin to dry;
• the plant withers;
• the fruits ripen poorly.

The causes of sunburn on tomato leaves are:

• not seasoned seedlings;
• water getting on tomato leaves during watering;
• prolonged exposure to direct sunlight;
• insufficient watering.

The most popular methods for getting rid of sunburn are described below:

• watering tomatoes only in the evening and under the root so that water does not fall on the leaves;
• more abundant watering of plants in hot weather;
• spraying the affected leaves with special preparations (for example, the Epin-Extra remedy is suitable).

Important! Tomato bushes, which received a sunburn, can no longer be completely restored. Despite the described methods of treatment, the tomato crop from the damaged plant will be much lower than expected.

White and brown spotting

Both diseases are classified as fungal and are able to quickly destroy the tomato bush. The signs of white and brown spotting are similar to each other, but in the second embodiment, white spots on the leaves of the plant gradually become brown.

The following symptoms indicate the presence of a fungal infection:

• white plaque forms on the leaves;
• first, the disease affects the lower leaves, and then spreads to the upper;
• tomatoes are softened and covered with mucus;
• leaves turn yellow and fall.

White and brown spotting are most often caused by such factors:

• improper watering;
• high humidity in the greenhouse;
• hot weather;
• the presence of pathogens in the soil.

To eliminate the disease, such actions are taken:

• the affected leaves are cut and destroyed;
• the stem and leaves are treated with special bactericidal preparations containing copper;
• carry out regular ventilation of the greenhouse;
• they treat the bushes with a solution of laundry soap (1 piece per bucket of water), a mixture of iodine and milk (15 drops of iodine per 0.5 l of milk) or a weak solution of potassium permanganate.

Did you know? Only 150 g of fresh tomatoes provide the adult's daily requirement for vitamin C.

Late blight

It belongs to one of the most common diseases of tomatoes. To save the crop, you need to start treatment for the disease immediately after the first signs.

Symptoms of late blight are:

• white fluffy coating on the bottom of the leaves;
• large brown spots on the top of the foliage;
• dry and brittle leaves;
• bare trunk as a result of falling leaves.

The causes of late blight are the following:

• a sharp difference in day and night temperatures in the greenhouse;
• the presence of potato plantings near tomatoes;
• last year's leftover seeds in the ground.

Late blight is treated in different ways:

• fertilization with high potassium content;
• pruning and destruction of affected leaves and bushes;
• processing of tomato bushes with a Bordeaux mixture or biofungicide;
• if there are fruits on the affected plant, they are disinfected with hot water (with a temperature of at least 60 ° C);
• folk remedies - tomato bushes are sprayed with garlic infusion or concentrated saline.

Other reasons

White spots on tomato leaves may indicate other problems with plants.

The reasons for their appearance may be:

• insufficient watering - the tomato bush lacks moisture, as a result of which its leaves weaken, light scorched areas form on them;
• lack of mineral fertilizers in the soil;
• white rot - occurs with high humidity and low air temperature in the greenhouse. For treatment, the affected tomato bushes are sprayed with a solution of copper sulfate or potassium permanganate.

Preventative measures

Any tomato disease is easier to prevent than to cure, so you need to pay attention to the prevention of white spots on these fruits.

Important! To determine the exact cause of the appearance of white spots on the leaves of tomatoes, you need to analyze all the conditions for growing plants.

Basic preventive measures are described below:

1. Hardening tomato seedlings before transplanting into the greenhouse.
2. Adequate watering of plants, especially in hot weather.
3. Airing the greenhouse after watering to reduce humidity.
4. Fertilizing with potassium, nitrogen and boron.
5. Thorough cleaning of last year's seeds and plant debris.
6. Disinfecting the land before planting tomato seedlings.
7. Location of a greenhouse with tomatoes away from potato beds.
8. Adequate free space around each tomato bush in the greenhouse.

With improper cultivation of tomatoes in greenhouse conditions, there is a high probability of the occurrence of diseases that can destroy the entire crop. To avoid this, it is enough to maintain conditions favorable for plants in the greenhouse and to begin timely treatment of tomato bushes when the first symptoms of diseases appear.