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How to get rid of late blight in a greenhouse in the spring. Is it necessary to treat a greenhouse against late blight in the fall? Folk remedies

Phytophthora, which has crossed the threshold of harmfulness, is a real scourge of gardeners. The disease is especially dangerous in limited space greenhouses and greenhouses. In 2-3 days, under optimal conditions for the spread of the disease, up to 70% of the tomato crop dies. Late blight is spread by zoospores that overwinter on the remains of leaves and stems different plants, in the soil, on supports and other construction and auxiliary parts of greenhouses and around the greenhouse space. They retain their viability for 3–5 years and are able to survive 20-30 degree frosts in the soil. Therefore, thorough annual disinfection of the greenhouse is extremely necessary, which will destroy late blight spores and prevent the appearance of the disease in the new season.

Phytophthora in a greenhouse - methods of prevention and control. © Suzanne Arruda

Preparing the greenhouse after late blight for the next season

In the fight against late blight, there is no separate pesticide that can be sprayed on the greenhouse - and the late blight is destroyed. The effectiveness of control is determined by a complex of autumn-spring work and constant diagnostics to identify diseases in cultivated plants, and timely implementation of protective measures.

Preparing the greenhouse for the next season can be divided into 2 stages:

external work on cleaning and disinfecting the territory and the frame of the greenhouse itself;
internal work to disinfect the frame, room and soil.

Preparing the greenhouse from the outside

After harvesting, clear the space around the greenhouse from broken containers and tools. All working tools used during the season (shovels, pruners, saws, knives, etc.) are repaired, disinfected and transferred to a specially designated dry room.

Collect and destroy leaves that have fallen around the greenhouse, dry remains of weeds and other debris in which zoospores of late blight and other diseases and pests can overwinter.

The top covering of the greenhouse is thoroughly washed to remove dust. You can use soap and water, but it is better to use disinfectants. To disinfect a greenhouse against late blight, use a solution of bleach or copper sulfate.

Attention! When working with disinfectants and other chemicals, be sure to take personal hygiene precautions.

If the greenhouse is covered with a covering that can be removed for the winter, after washing it is carefully removed, rolled up and stored in a dry, disinfected room. They inspect the frame of the greenhouse and carry out the necessary repairs.

If the greenhouse is covered with polycarbonate or glazed, then repair work is carried out to replace glass or restore damaged parts of polycarbonate. The cracks in the transoms are sealed with sealant. Then rinse thoroughly outside greenhouse covering and the frame itself. During the winter, snow deposits are constantly removed from the greenhouse.

To reduce the infestation of the territorial space near the greenhouse, nightshades are never planted near the greenhouse, especially potatoes (the crop most affected by late blight).

Instructions for carrying out interior work in a greenhouse

In order to properly prepare and disinfect the interior of the greenhouse from late blight, it is more practical to carry out all work in the following order:

Remove the entire portable open irrigation system (hoses, irrigation barrels, containers, tools, etc.). They are washed, disinfected and transferred to the utility room.

Clear the greenhouse room of shelves, boards, racks, pegs, and remnants of twine. Sorted, necessarily disinfected, dried and stored in indoors.

Clear the beds of plant debris - potential sources of late blight. Remove tops and roots, uncleaned, diseased, unripe fruits and other plant debris. Healthy tops (for example, cucumbers) can be placed in compost heaps. All vegetation and debris removed from the greenhouse, especially if the crops have been affected by late blight, must be burned.

Before disinfection, the greenhouse is “bathed”, ridding the room of dust and dirt. Wash the inner surface, including the frame, with a soap solution or with the addition of copper sulfate. Galvanized metal structures are washed with a 9% vinegar solution.

After execution general works prepare disinfectant solutions against late blight and the necessary equipment.

With a prepared solution of freshly slaked lime, from the back wall of the greenhouse to the doors, they literally coat all wooden structures of the greenhouse with a thick slurry, not missing hard-to-reach places, cracks, ceilings, fastenings, supporting poles, etc. The metal frame or individual metal parts in the greenhouse must be painted. If painting is not possible, then they are treated with Bordeaux mixture.

If in the fall you did not have time to disinfect the greenhouse from late blight, then in the spring, 3-4 weeks before the start of seasonal work, the greenhouse is washed, the wooden floors and the rest of the frame are whitened with freshly slaked lime, and the metal frames are treated with 9% vinegar. Keep the room closed for 2 to 5 days, ventilate and treat with biofungicides (see the section “Use of biological preparations” below).

Remember! When working with chemical solutions, be sure to follow the rules of personal sanitary protection: respirator, goggles, hat, gloves, shoes, closed outer clothing.

Methods for disinfecting greenhouse premises against late blight

Methods for disinfecting a greenhouse can be divided into:

chemical;
biological;
temperature;
complex.

Chemical treatment

The most accessible disinfection solutions for premises are:

bleach;
slaked lime;
concentrated solution of copper sulfate;
sulfur bombs;
chemical fungicides.

For cooking bleach 0.5-1.0 kg of dry matter is dissolved in 10 liters of water. Leave for 3-4 hours, filter and spray the entire interior, thoroughly coat all wooden structures (additional protection against rotting). Close hermetically for 2-3 days, then ventilate. After ventilation from bleach fumes, the wooden frame is treated with a 5-10% solution of copper sulfate, and the metal frame is painted (at least every 2-3 years).

You can disinfect the room with a solution slaked lime. To prepare a slaked lime solution, use the following ingredients: 3-4 kg of freshly slaked lime are mixed with 0.5 kg of copper sulfate and 10 liters of water. A thick suspension is carefully used to cover the wooden frame, brickwork and all places where pathogenic microflora can overwinter harmlessly.

Copper sulfate copes well with late blight. Prepare a saturated solution of 100-150 g of vitriol per 10 liters of water and carefully clean all areas of accumulation of pathogenic microflora with this composition.

From in various ways disinfection the most popular is fumigation with lump sulfur. The method takes significantly less time and labor costs. Smoke penetrates into all hard-to-reach places in the room, leaving late blight no chance of survival. Lumps of sulfur of 100-150 g each are laid out on iron trays. Trays with sulfur mixed with kerosene, place one per 1.0-1.5 square meters. m of greenhouse area and set it on fire, moving from the back wall to the exit from the room.

The room treated from late blight is hermetically sealed and left for 4-5 days, then ventilated. It is necessary to work in a respirator, goggles and protective clothing. It is important to remember that sulfur dioxide, which is formed when sulfur is burned, is dangerous to human and animal health.

Sulfur fumigation can be carried out with ready-made checkers “Fas”, “Climate”, “Vulcan”. The method of use is described in detail on the packaging.

Remember! If the frame of the greenhouse is metal and not painted, sulfur fumigation cannot be used due to the activation of corrosion processes.

Market chemicals offers a range of universal effective chemical fungicides, which quickly disinfect the room and soil in the greenhouse from late blight. They contain compounds of sulfur, iron, mercury, copper, manganese and others, which pose a great danger to the life and health of humans and animals.

Therefore, it is better not to use them in private possessions or to use them with great caution, strictly following all recommendations for working with such substances. The conditions for working with fungicides and other requirements are always written on the packaging or in the form of a recommendation appendix.

Chemical fungicides against late blight can be used in the form of fumigation or spraying, which is recommended to be carried out in the morning or evening at a room temperature within +10...+25°C.

Of the chemical fungicides against late blight, we can recommend for disinfecting the premises by spraying:

"Ecocid-S", 5% solution;
"Virkon-S", 2-3% solution;
"Virocid", 1% solution.
"Oxychom", 2-3% solution;
"Abiga-pik", 3-5% solution.

The premises are sprayed with working solutions, left closed for 2-3 days, then ventilated and dried.

Chloropicrin is used for aeration of premises, consuming 15-40 g of the substance per cubic meter. The treatment is carried out at a temperature not lower than +12°C. The room is kept closed for 3-5 days, then ventilated.

Temperature treatment

Application chemicals for late blight can be replaced solar “roasting” of the room. If autumn is hot and dry, seal the room hermetically. The temperature inside rises to +35°C. The room is kept hermetically sealed from several hours to 2–3 days. Zoospores at a temperature of +30°C reduce their activity, and at +35°C they begin to die. Naturally, the source of the disease does not die completely, but the room is 70-80% cleared of pathogens.

In cold regions it is actively used to combat late blight and other diseases. "freezing" the greenhouse. It is effective for small greenhouses. During the winter cold, the greenhouse is left open for several days. There is no need to cover the soil with snow, since phytophthora zoospores will overwinter comfortably under its layer. After freezing, the soil in the greenhouse is covered with snow.

Use of biological drugs

At home, especially if the greenhouses are small, it is better to use biological preparations to disinfect the greenhouse from late blight. The drugs are developed on the basis of positive microflora, harmless to humans, which has the ability to suppress fungal diseases for several years. The only condition: biofungicides do not work when low temperatures. Treatment of the room with biofungicide solutions should be carried out at a room temperature not lower than +12…+14°C.

Used to disinfect premises biological product "Fitop-Flora-S". 100 g of the substance is dissolved in 10 liters of dechlorinated water and the room is thoroughly sprayed. After 1.5-2.0 weeks, spraying is repeated.

Biofungicide "Fitosporin" classified as universal disinfectants for greenhouses. It is used to treat premises, soil and plants during the growing season. To spray the room, prepare a saturated working solution (50 ml per 10 liters of water) and thoroughly treat the room. After spraying, keep the greenhouse closed for 4-5 days. Then further work is carried out.

The greenhouse premises are treated in the same way. "Trichodermin", "Bactofit" and other biological products.

Complete greenhouse treatment

IN recent years To combat late blight, greenhouse growers use a set of measures: “roasting”, “freezing” the premises, together with treating plants during the season with biological products “Fitosporin-M”, “Alirin-B”, “Krezacin”, “Trichoplant”, “Baktofit”, “ Planzir”, etc. The same preparations are also effective in disinfecting premises and soil. Detailed dosages and conditions for use of biofungicides are described in detail on the packaging, insert or accompanying recommendations.

For home greenhouses, the most acceptable in terms of labor costs, cost and health safety is complex use temperature and biological methods processing the premises, it provides effective protection against late blight and allows you to harvest organic vegetables.

A set of preventive measures against late blight in a greenhouse is the best protection for plants in the coming season. ©Primarady

Disinfection of greenhouse soil from late blight

In a confined space, greenhouse soil quickly loses its agronomic structure, reduces fertility, increases acidity, and accumulates pathogenic flora and fauna. To increase the duration of use of the greenhouse, the greenhouse soil must be systematically regenerated. Soil improvement is carried out in several ways.

The most harmless method for the environment, humans and animals is complete or partial replacement of the soil in the greenhouse. The method is very simple, but labor-intensive and is more suitable for small greenhouses. Usually, once every 2-3 years (can be done annually), the top 10-25 cm layer of soil is carefully removed and taken to a prepared place, where they are formed layer cake» from waste soil, dry healthy tops, autumn leaves, compost.

Each layer 5-15 cm high is poured into warm period water or a solution of the preparations “Baikal EM-1”, “Ekomik”, “Trichoplant”, “Azotofit”, etc. Composting using solutions of these biological products helps to destroy negative microflora and more quickly process plant material.

There is another way to improve the health of the top layer of soil in a greenhouse. Old soil in a layer of 15-20 cm can literally be sorted out or sifted through sieves with wide holes (0.3-0.5 cm). The soil will be cleared of excess roots, rotting residues, and some pests. The cleaned soil is sown with green manure.

In dachas and personal garden plots it is better to use biological method soil disinfection. It is especially effective in combination with preliminary temperature treatment of the soil.

After treating the greenhouse with bleach, slaked lime, and copper sulfate, part of the solution falls on the soil. Mix the top layer by loosening. We expose the dried soil to the sun. High temperature in dried and sun-warmed soil (+30...+35°C), it will destroy a significant part of the pathogenic microflora and improve the health of the soil.

If you haven’t had time to carry out work to disinfect the soil from late blight since the fall, then they should be done 2-4 weeks before the start of seasonal work in the spring. The soil is watered with hot water and covered with film for deeper steaming.

Both methods of hot soil disinfection destroy not only part of the pathogenic, but also beneficial microflora. After such disinfection, the soil needs to be reanimated. To restore beneficial microflora, the soil is moistened if necessary, brought to a temperature of +12...+14°C and treated with a solution of “Baikal EM-1”, “Ekomik”, “Siyanie” or scattered “Emochka-Bokashi”, covered with a rake and covered with a covering material .

In a warm, humid environment, effective microorganisms (EM) begin to multiply intensively, using pathogenic microflora as food. To maintain a healthy soil level during seasonal work, approximately once every 2-4 weeks with watering, the same biofungicides are added to the soil as for treating plants - “Gamair”, “Alirin-B”, “Trichoplant”, “Gaupsin”, “Fitosporin-M”, etc. How to prepare solutions of biofungicides for soil treatment is indicated in the accompanying recommendations or on the packaging of the drug.

At home, even those in a hurry who like to do everything quickly are not recommended to disinfect greenhouse soil with chemicals.

From chemical methods tillage against late blight in private greenhouses, it is permissible to treat the soil with a hot solution of potassium permanganate (dark pink color) or a solution of copper sulfate prepared at the rate of 25-30 g of the drug per 10 liters of water. 2-3 days after processing the soil, digging is carried out using an incomplete shovel and green manure is sown. It is not recommended to use these methods of soil disinfection frequently and in large concentrations. Manganese and copper contained in salts accumulate in the soil and inhibit plants.

A greenhouse in which plants suffered from late blight requires special treatment after harvest, both inside and outside. © Country Folks Grower

Ways to re-infect a greenhouse with late blight

Despite the disinfection of the greenhouse, late blight may appear in the new season on tomatoes and other nightshades. Ways of re-infection:

low-quality and not disinfected seed material;
diseased seedlings;
the introduction of Phytophthora zoospores by the wind from open areas and neighboring vegetable gardens through open transoms during ventilation;
the infection can enter the soil via droplets during high humidity in the greenhouse, especially if the latter has not been well disinfected;
the source of infection may be undisinfected tools and auxiliary devices (hoses, containers, shovels, etc.).

How to find out that late blight has appeared in a greenhouse ?

Late blight infection is most pronounced on tomatoes, the most common crop grown in protected soil conditions.

The lower part of the leaves located close to the soil is covered with individual whitish spots of cobwebs. They merge and acquire a brownish tint. The leaves curl, dry out, and fall off. Sometimes the disease begins with damage to the edges of the upper leaf blade with brownish spots.

After 2-3 days, the stems and petioles become covered with brown spots. This sign indicates the entry of late blight into the most active phase of reproduction. During this period, lightning damage to all tops, inflorescences and fruits is observed.

The fruits are initially covered with dark spots located under the skin of the fruit. Their color under the skin is brownish-red. The spots quickly soften, and the tomatoes begin to rot, caused by accompanying rot.

The only way to save the crop from late blight is by urgent harvesting and planting for ripening. How to properly lay fruits for ripening is described in the article.

Remember! Tomatoes that are even slightly damaged by late blight (that is, in the dark spot stage) should not be used for food.

If timely plant protection measures are not taken, the epiphytotic propagation of late blight will destroy the crop in a matter of days.

Conditions for the propagation of Phytophthora zoospores in a greenhouse

Favorable conditions for the activation and reproduction of Phytophthora zoospores in a greenhouse and other enclosed spaces are:

increased unregulated humidity;
drops from greenhouse cover;
differences between night and day temperatures.

If the air humidity in the greenhouse is above 75%, and the air temperature is +12...+15°C, then zoospores begin to actively reproduce. Together with the drop they fall into the soil. Incubation period lasts 7-12 days and an outbreak of the disease occurs. Late blight cannot be destroyed forever. She keeps coming back.

Therefore, in order to obtain a full-fledged healthy harvest, along with systematic disinfection of the greenhouse, it is necessary to carry out protective measures during the vegetable growing season to preserve tomato fruits from late blight.

Read more about protecting tomatoes from late blight in the articles.

One of the most dangerous diseases of tomatoes is late blight, and even their cultivation in a greenhouse does not relieve this vegetable from the threat of disease. What are the reasons for the development of late blight in polycarbonate greenhouses and how to deal with it, advice from specialists and experienced gardeners presented in the photo and video will tell you.

Late blight in the greenhouse: causes of the disease

Late blight infection is indicated by the appearance of dark spots on their leaves, which then spread to the stems, flowers and fruits, causing them to rot and fall off. The disease can develop so quickly that in just a week it can lead to the death of the entire tomato crop. The following conditions contribute to the development of the disease:

temperature changes in the greenhouse due to severe overheating V daytime and its significant reduction at night, especially if the windows and doors of the greenhouse were left open at night;
increased humidity in the greenhouse caused by frequent watering or the use of sprinkling;
increased alkali content in the soil caused by non-compliance with proportions when liming acidic soils;
thickening caused by failure to maintain the distance between plantings, failure to plant and thin the crown;
excess nitrogen and lack of other minerals: phosphorus, copper, potassium and others in the soil, which leads to weakening of plants and slower development;
joint cultivation of several types of nightshade crops in one greenhouse; the proximity of tomatoes and potatoes is especially dangerous.

Attention! Phytophthora spores spread easily by air and die quickly - within a few hours, when a hot, dry microclimate is created in a polycarbonate greenhouse.

Late blight is the most dangerous disease for tomatoes

Preventive measures

Prevention of late blight is the best way to spread the disease in a confined greenhouse space. A set of actions aimed at preventing the development of late blight includes:

1. Autumn processing greenhouses, consisting of cleaning and destroying the remains of plants and auxiliary elements - pegs, supports, trellises, treating the premises with disinfectants, sulfur bombs.

2. Disinfecting the soil by steaming it with boiling water or treating it with chemicals.

Attention! Effective method protection against late blight is the annual renewal of the soil layer with a depth of 5 cm to a new one.

3. Selection of disease-tolerant hybrid forms and varieties, as well as pre-sowing half-hour disinfection treatment of tomato seeds. Growing ultra-early varieties of tomatoes and cherry tomatoes will also help avoid the spread of late blight.

4. Additional spring pre-sowing soil treatment with tobacco or garlic infusion.

Attention! If disinfectant cleaning of the soil was not carried out in the fall, then in the spring before planting, you should definitely treat the soil with a solution of bleach or copper sulfate.

To prevent late blight, it is necessary to carry out preventive measures

5. Compliance with the conditions of agricultural technology - crop rotation, selection of plants for partner and neighbor plantings, planting density, pinching, tying, thinning the crown, removing fallen plants.

6. Maintaining a stable temperature in the greenhouse, without sudden changes, watering in the morning, avoiding waterlogging, organizing ventilation.

7. Two to four single treatment with fungicidal preparations - “Acrobat”, “Zaslon”, “Bio-fungicide” “Barrier”, “Pennkozeb” and others. It is recommended to carry out the first spraying after the transplanted seedlings have taken root in the new location, and repeat spraying after 2-3 weeks.

Attention! Treatment against late blight with industrial preparations is possible no less than 3 weeks before harvest. To avoid adaptation of pathogens to the drug used, it is recommended to change it annually to another one.

Late blight can be combated using medications. as well as folk remedies

Traditional methods

The use of home remedies to control and prevent late blight in the greenhouse allows you to avoid the accumulation of dangerous substances in the fruits and at the same time cope with the disease.

The most effective, according to vegetable growers, are:

Carrying out preventive measures is the most important condition for obtaining good yields of tomatoes when grown in polycarbonate greenhouse. If the disease appears when the tomatoes have almost reached ripeness, the best solution would be to harvest the unripe crop.

Treatment of a greenhouse against late blight - video

Everyone who grows crops on their plot knows what late blight is. The late blight fungus mercilessly affects almost all types of plants of the nightshade family, but does not disdain some others. Particularly favorable conditions for its development are in greenhouses and film shelters for growing plants. The problem of late blight under the film can persist from year to year! Now I’ll tell you in detail how to treat a greenhouse after late blight in the fall.

What is late blight or late blight

This plant disease is of a bacterial nature; late blight is a fungus that attacks the leaves, stems, and ovaries of healthy plants. If the development of the disease is not stopped at the very beginning, it progresses, gradually infecting neighboring crops and spreading throughout the entire area. Fatal outcome for plants it can occur very quickly if no measures are taken.

The most favorable conditions for the development of late blight are warm humid climate. Rainy summer– ideal for intensive growth of late blight mycelium and infestation of large areas of seedlings. And in greenhouse conditions, the appearance and growth of fungus is simply inevitable, due to the constant release of condensation on the film and heat inside the shelter.

If you want to grow healthy seedlings and get high-quality fruits, a constant fight against late blight in the greenhouse is inevitable. There are several popular methods that allow you to neutralize the fungus completely or in significant quantities.

The best methods of struggle and popular remedies

The effectiveness of late blight destruction depends on the methodical nature of your actions and the careful implementation of a set of measures. There is little that can be solved here by treatment alone; it is important to take a multi-faceted approach to removing the disease from the greenhouse.
agricultural technology in a greenhouse

Autumn is the time to get the greenhouse in order after summer work. In order to confidently plant fresh seedlings in the spring, you need to perform a number of certain procedures to properly prepare the greenhouse for wintering. What needs to be done for this?

Chemical control methods

Chemical preparations used to treat the greenhouse structure and soil can reliably get rid of late blight.

The simplest disinfectant available to every gardener - soap solution.
Of course, expect from him high efficiency it shouldn’t, but it is quite possible to clean the surfaces and prepare them for the application of more aggressive preparations. In addition, soap also has a disinfectant effect.

A more serious solution can be called copper sulfate.
It is diluted in approximately 100 grams per bucket of water and carefully treated all surfaces - greenhouse covering, supporting structures, doors, etc.

For greenhouses with a base made of wood, the best option would be treatment with bleach solution.
It must be prepared in advance; approximately 300-400 grams of lime must be diluted in a bucket clean water, stir well and leave for five to six hours. This solution can also be used to treat the surface of the greenhouse and cover the wooden frame (which will also protect it from wood pests). After disinfection with bleach, it is advisable to keep the greenhouse closed for two to three days for greater efficiency.

Well, and, of course, many gardeners are now using more modern methods fight against late blight. This fungicide treatment– systemic drugs that affect the nervous system of pests, thereby neutralizing them.
Often used for disinfecting greenhouses made of polycarbonate or glass. Fungicides must be used carefully, without oversaturating the soil with them, as they kill not only harmful, but also beneficial bacteria, which can lead to soil depletion.

Sulfur checker

Fumigation of a greenhouse room with a sulfur bomb - proven and sufficient effective remedy against late blight. This method is affordable and easy to implement. It is enough to set fire to a sulfur bomb inside the greenhouse, tightly close the doors and other existing cracks or openings. For complete processing, one day of exposure is enough.

The disadvantage of this method is that sulfur smoke, taking into account the moisture in the greenhouse, forms a chemical compound - acid, which negatively affects the metal parts of the structure. If there are any in the greenhouse, they need to be mandatory protect from the harmful effects of sulfur bombs. For example, generously lubricate with grease or other similar products.

The dangerous late blight fungus, having settled in a greenhouse, negatively affects the quality of the future harvest. Infection of plants is indicated by black spots on the fruits, which gradually increase in size, affecting the vegetable completely, and then spreading to healthy plants. It is possible to get rid of late blight in a greenhouse (including polycarbonate), but it is important to begin this immediately after discovering the “enemy”. It is also necessary to adhere certain rules, which will help not only win this unequal battle, but also prevent the disease.

Danger of disease

Even greenhouse plants can become infected with late blight. Externally, the fungus is a white cobweb that entangles the inside of the plant. There it grows and develops, taking away the vitality of the plant. Ripe spores are released outside, where they are transported with the help of water to neighboring plants. After this, a new cycle of fungal development begins.

Even severe frosts are not afraid of spores: they wait out the winter, and when the air temperature rises to 10°C they begin to actively develop.

Symptoms of the lesion

Before you throw all your energy into fighting the fungus, you need to make sure that it has actually settled in the room. At first, late blight does not appear outwardly in the greenhouse. But gradually, as the disease progresses, external changes. The first alarming symptom is yellowing of the foliage. Then:

the appearance of brown spots on the green mass of the plant;
the formation of a white fluffy coating on the inside of the leaves;
the appearance of black spots, as if slightly pressed into the fruit;
fruit formation irregular shape, long harvest ripening;
rotting and softening of fruits, the appearance of an unpleasant odor.

The main causes of late blight are lack of fresh air (poor ventilation), waterlogging and non-compliance with temperature regime(most often a decrease in temperature).

Unfortunately, it will not be possible to save the affected plant. But to expel the micropest from environment not only is it possible, but even necessary. Its spores in the soil survive even negative temperatures. Therefore, you should not hope for them to freeze in an unheated room. To avoid crop loss from late blight next year, it is necessary to treat the greenhouse immediately after harvesting the fruits.

If you find late blight in a greenhouse or greenhouse, what to do depends on what stage of development the crops are at. The ripe crop is harvested and the room is disinfected. In the case when the fruits are not yet ripe, their development is supported by folk remedies, and in the autumn the entire greenhouse space is disinfected.

Folk remedies

It is often not recommended to use chemicals and preparations with copper. After all, while remaining in the soil, they end up in fruits, and then in human body, negatively affecting his health. Effectively combat late blight in a greenhouse with folk remedies:

Garlic. To prepare the infusion, you need to add 0.5 tsp to 1.5 cups of peeled garlic cloves. potassium permanganate and pour in 2 liters of water. Then the container is closed and left for half an hour. After this, the infusion is diluted with a bucket of water and used for watering in an amount of 0.5 liters for each bush.
Dairy products. Milk is mixed with water in proportions of 1:10, and then used to spray the bushes. Lactic acid bacteria stop the development of the fungus, which allows the bush to continue development and fruiting. For the same purpose, it is good to use whey (mixed with water in a 1:1 ratio). The spraying procedure is carried out twice a month all summer.

Salt. Dissolve a glass of the substance in a bucket of water and spray the plants. After drying, a protective film forms on the bushes, which prevents the penetration of pathogenic organisms.
Yeast. Mix with water in a ratio of 1:10 and use for irrigation.
Ash. Sprinkle the soil before watering or spray the bushes with a solution.
Copper. Copper wire can be hung along the bushes or wrapped around them, threaded through the stem.

Iodine in a greenhouse against late blight

Antiseptics are used not only to disinfect wounds. You can use iodine in a greenhouse against late blight by spraying the solution on plants. Its use in conjunction with dairy products will be effective:

With whey: add a drop of iodine for each liter of product. The resulting solution is diluted with water in a ratio of 1:10 in the case of watering at the roots or 1:3 for spraying.
With milk: take 1 liter of low-fat product and 20 drops of iodine per bucket of water. Spray the solution twice a month.

Spraying in the greenhouse is carried out early in the morning or in the evening. It is important to spray with fine sprays so that the surface is treated better. However, too much moisture will not be very beneficial.
Interesting method using iodine against late blight in a greenhouse in the video below.

Greenhouse treatment

There is a very high probability that fungal spores will overwinter in greenhouse soil, plant debris or structural elements. Therefore, all disinfection measures are aimed at treating the entire greenhouse space. Careful work in this direction will not only get rid of late blight, but also prevent its recurrence.

Conventionally, processing agents are divided into biological, chemical and temperature. The first ones are used as preventive protective measures, the second ones are used to treat the structure and soil, and the third ones disinfect the soil. Any means are used only after thoroughly cleaning the room.

At this stage, all instruments are removed and disinfected. Clear the greenhouse of all materials used in the growing process. All plant residues along with the roots are collected and burned to destroy the fungus remaining in them.

To get rid of fungal spores on a greenhouse structure, it is necessary to disinfect it. For greater efficiency, it is necessary to seal the structure and cover up all the cracks found. When carrying out disinfection, the following rules must be observed:

The air temperature must be at least 10°C, otherwise the greenhouse treatment will not be productive enough.
It is advisable to spray all surfaces with water to increase the toxic properties of the substance used.
It is necessary to use protective equipment: a gas mask or a respirator. This is due to the high toxicity of the drug.

The greenhouse against late blight is fumigated with sulfur bombs or lump sulfur. The drug is used at a rate of 50-80 g per 1 m³. If found spider mite, then the dosage increases to 150 g for the same volume.

You can also use regular sulfur to combat late blight. Metal sheets with sulfur are placed inside along the perimeter of the greenhouse and set on fire. Then the room is closed for 3 days. After this, ventilate well.

You can carry out wet treatment of the greenhouse (it is especially good for metal structures, which sulfur destroys quite quickly). In this case, all surfaces are thoroughly sprayed with a solution of bleach (0.4 kg per 10 liters of water, infused for 4 hours) or a solution of copper sulfate (75 g for the same amount of water).

Greenhouse surfaces are treated against late blight and slaked lime solution. All parts of the structure are coated with it. Metal parts are additionally treated with boiling water, and wooden parts are cleaned with a brush. After whitewashing, the room is ventilated, and after half a month the procedure is repeated.

Soil disinfection

Before disinfection, the soil must be dug up.

Completely replace the top layer, fertilize and then disinfect in different ways:

First, they pour boiling water over it and then cover it with polyethylene to destroy all pathogens.
Treat with a solution of copper sulfate (a tablespoon per 10 liters of water). It is important to remember that frequent use of vitriol contributes to the accumulation of copper in the soil and plants. And this negatively affects human health.
Add dry lime. This cannot be done before planting bushes (quicklime powder will negatively affect the growth and development of the plant), so it is processed in this way only in the fall.
Disinfect with formaldehyde. For this purpose, they first dig ditches, pour the substance into them, and then cover them with earth and leave them for a couple of weeks. After this, the room is ventilated for half a month.
Special solutions that are designed to disinfect soil in a greenhouse.

Winter care activities

Winter is a very harsh test for plants in heated greenhouses. By this time, the room is carefully sealed to prevent cold air from entering. The result is a lack of fresh air, high humidity and cool temperatures, which contribute to the development of late blight. The only option to prevent the disease is ventilation, which will increase the amount of oxygen supplied. It is important to ventilate at least a fifth of the room.

Spring disinfection of the greenhouse

In the spring, the inside of the room is first wiped with a solution of freshly slaked lime, to which vitriol is added. Together with this procedure, all mosses that appear on the frame are destroyed. After this, thoroughly wash all glass surfaces.

All surfaces are thoroughly washed with soapy water: both internal and external, without missing a single crack. To treat walls and shelves, you can also use solutions of garlic, mustard powder and tobacco ash.

Prevention of late blight

Growing plants in a polycarbonate greenhouse has several advantages. Among them is the ability to create certain conditions that will not allow harmful microorganisms to develop normally. In order not to be afraid of the appearance of late blight on tomatoes in a polycarbonate greenhouse, you must adhere to the following rules:

mulch the soil;
avoid dense plantings;
tie up tall bushes so that the root part is constantly ventilated;
Remove all excess foliage and unnecessary shoots.

And in order to avoid late blight getting into the greenhouse from the outside, it will be necessary to plant the main carriers of the disease - tomatoes and potatoes - away from the room. And then you can sleep peacefully, without worrying about this insidious disease.