How and with what to treat tomatoes against late blight in open ground: top best products and rules for spraying tomatoes

Late blight is one of the most common diseases of tomatoes. It is caused by the late blight fungus. The entire above-ground part of diseased plants, including fruits, becomes covered with brown spots. The leaves begin to wither and the berries begin to rot. Ultimately, this leads to the death of plants and damage to the crop.

It is almost impossible to cure late blight. However, there are many methods to prevent this disease. Vegetable growers use both purchased and homemade preparations. How to treat tomatoes against late blight in open ground - read on.

Features of the prevention and treatment of late blight

Phytophthora is a dangerous fungus, the main cause of death of nightshade crops.. It attacks tomatoes in cool, damp weather and causes plant death. If the disease has managed to affect the ovaries and fruits, then it will not be possible to save the plants.

In the early stages of the disease, it is possible to save the affected plants. To protect your garden beds from late blight, you need to know its signs.:

1. A whitish coating forms on the leaves and stems, which later darkens and turns into brown or black dry spots. The above-ground part of the plants begins to wither.
2. The fruits are covered with small black spots. Over time, they enlarge, acquire a brown tint and begin to rot.

Such signs appear within a couple of days after infection. Their appearance is easy to predict, knowing the causes of the disease:

1. Humidity and temperature. In hot, dry weather, fungal spores are in a “dormant” state, so under such conditions tomatoes do not get sick. After prolonged rains, cold snaps or temperature changes, late blight is activated, and the probability of plant infection increases to 100%. That is, late blight infection occurs in damp, cool weather.
2. Poor air exchange and violation of watering rules. Stagnant moisture and lack of air are ideal conditions for the development of late blight.
3. Proximity of potato plantings. The fungus overwinters in potato tubers. This crop is a carrier of late blight.
4. Inappropriate soil acidity levels. Highly alkaline soils are optimal for the development of late blight.
5. Micronutrient deficiencies. This negatively affects the immunity of tomatoes and makes them more susceptible to diseases.
6. Application excessive amounts of nitrogen fertilizing. An excess of this substance in the soil stimulates the development of fungus. This factor also provokes the formation of a large amount of greenery, which interferes with normal air exchange.

The fewer of the described factors around tomatoes, the lower the likelihood their late blight infection. Therefore, the main task of prevention is to provide plants with optimal conditions for development.

Treatment of plants is possible only in the early stages development of diseases. If there are many affected areas on the plant, such bushes will have to be completely removed and burned.

Methods to combat late blight

For the prevention of late blight three types of funds are used:

1. Folk remedies. Considered the safest. They are suitable for spraying plants even during the period of fruit set and ripening. They are effective for preventing disease, but they will not save diseased plants.
2. Pharmacy drugs. Less safe than folk remedies, but do not cause damage to the environment and do not lead to severe poisoning. They are used until the formation of ovaries. Used primarily for disease prevention. At the initial stages of disease development, there is a chance to get rid of the fungus.
3. Chemicals. Many of them are toxic to humans, so plants are sprayed with them before the inflorescences appear. Rarely used for prevention, but effective in the initial stages of disease development.

Folk remedies

Folk remedies are the safest and most accessible. They are easy to prepare from products that are available in every home. The use of such preparations is allowed even during the fruiting period of tomatoes; they do not poison the fruits and are safe for the environment.

The list includes the most effective recipes for spraying plantings:

1. Salt solution. To prepare it, dissolve a glass of salt in 5 liters of water. The resulting product is sprayed onto tomato bushes. This salt protection will not allow fungal spores to develop.
2. Ash-soap solution. To prepare it, add 2 tbsp to a 5 liter bucket of water. ash. The composition is infused for three days. Then rub half a bar of laundry soap into the mixture. Plants are sprayed with this mixture once every two weeks.
3. Dairy products. For 10 liters of water take 1.5 liters of kefir, sour milk or whey. The above-ground part of the plant is treated with this mixture in the evening.
4. Garlic infusion. Add 1.5 tbsp to a bucket of water. chopped garlic heads and arrows. The mixture is infused for 24 hours, and then 0.5 tsp is added to it. potassium permanganate. The plants are treated with the product the first time before the formation of ovaries, the second time after the appearance of 1 ovary.Then every two weeks.
5. Polypore decoction. 100 g of mushroom are ground in a meat grinder and brewed in 1 liter. boiling water The product is allowed to brew for 3-4 hours, after which it is filtered and used for spraying.
6. Copper calcination. The copper wire is calcined, cut into pieces 3-4 cm long and pierced the stem with it at a distance of 10 cm from the soil surface. The ends of the wire are bent down. The method is only suitable for mature plants with fruits.
7. Soda solution. For 1 liter of water add 1 tbsp. l. soda

Home remedies are used mainly for prevention against late blight. They can also be used if the fungus has infected only a few leaves on the plants. In this case, the affected greens are removed.

Note! Many of the described remedies help fight not only late blight, but also other diseases and pests.

Chemicals

Chemicals contain a high concentration of substances that kill late blight. Their use is effective not only for prevention, but also for treatment of the disease.

Such products contain harmful substances that penetrate into the soil and groundwater. When tomatoes bear fruit, their use is unacceptable. Gardeners try not to use such drugs unless absolutely necessary and in the early stages.

The most popular chemicals to combat late blight:

1. "Ekopin". Take 1 g of product per bucket of water.
2. "Infinito". Add 5 tsp to 10 liters of water. drug.
3. "Metaxyl". 40 g of product are diluted in 5 liters of water.
4. "Ditan M-45". 16 g of the substance is added to 10 liters of water.
5. "Acrobat". 40 g of substance are dissolved in 10 liters of liquid.
6. "Fitosporin". 5 g of powder or 15 drops are diluted in 10 liters of water.
7. "Metranidazole" or "Trichopolus". Add 20 crushed tablets to 10 liters of water.

These drugs are used not only for spraying tomatoes, but also for watering soil infected with late blight.

Pharmacy products

Pharmacy products are used not only to treat people. They I will also help tomatoes with late blight. The main thing is to use them correctly:

1. Solution boric acid. To prepare it, 1 tsp. boric acid is dissolved in a bucket of water.
2. Iodine. Add 30 drops of iodine to a bucket of water. To increase the effectiveness of the product, add 1 liter of milk to it.
3. Potassium chloride solution. For 10 liters of water take 10 g of potassium chloride.
4. "Furacilin". 20 Furacilin tablets are crushed and dissolved in a bucket of water.
5. Potassium permanganate. Tomatoes are sprayed with a light pink solution of potassium permanganate. To do this, take 10 g of powder per 10 liters of water. This product is also used to disinfect the soil; in this case, a dark pink solution is prepared.

In terms of effectiveness, pharmaceutical preparations are close to home remedies. They are used mainly for prevention.

Which product to choose depending on the month

At different periods of tomato development, different means are used.. This is important to consider when choosing drugs:

1. Chemicals are used before flowering and the formation of the first ovaries. They are used in May and June. They also water the ground in the fall after harvesting in the beds where tomatoes infected with late blight grew. "Fitosporin" is also used in the spring, before planting. This product is also suitable for treating seeds.
2. If the plants do not get sick, then in the early stages of their development it is better to use safer home remedies. They are sprayed with a solution of potassium permanganate, iodine, fermented milk products, etc.At this stage, salt and copper wire are not used.
3. In July and August, when tomatoes bloom and form their first ovaries, it is better to avoid chemicals. In the early stages of disease development, folk recipes will be effective. Especially often, punctures with copper wire are used for adult tomatoes.
4. If the late blight epidemic began at the end of July or August, then the plants are sprayed with a strong salt solution. This method will help preserve the harvest, but will cause the greenery to wither.

How to treat tomatoes against late blight in open ground

To protect tomatoes from late blight, It is important to follow the prevention schedule. This minimizes the likelihood of plant infection:

1. The first treatment is carried out before the inflorescences appear. Both homemade and chemical preparations are used.
2. The tomatoes are sprayed a second time after the first ovary appears. It is allowed to use only pharmaceutical or folk remedies.
3. Then spraying is carried out every two weeks.

This schedule is suitable for the prevention of late blight. If the plants are already sick, treatment is carried out more often.

It is possible to stop the development of late blight in the early stages. To do this, the plants are carefully inspected and the affected leaves are removed. The cut areas are sprinkled with ash.

Bushes with affected stems are completely removed. They are taken off site and burned. After this, healthy plantings are treated weekly. The soil is watered with a solution of potassium permanganate, "Fitosporin"or copper sulfate.

Before tillage With anti-phytophthora agents, water the soil with ordinary warm water. This will prevent the roots from rotting.

Preventive measures

There are a number of rules that must be followed, to avoid plant infection with late blight:

1. Plants are provided with proper watering. The water should not be cold. It is important not to allow water to stagnate. The soil is moistened 1-2 times a week. Water tomatoes only at the roots; getting water on the leaves will increase the risk of developing diseases.
2. The soil is loosened after rainfall and watering. This is necessary to restore normal root air exchange and prevent moisture stagnation.
3. Mulching. The beds are covered with a layer of straw, hay or burlap. This will protect the plants from infections and create an optimal level of humidity.
4. During frosts, as well as at the end of summer during cold spells at night, it is recommended to cover the beds with film at night. This will protect the plantings from cold dew.
5. Maintaining crop rotation is another important step. Tomatoes are not planted in beds where nightshade crops grew last year. It is not recommended to plant potatoes next to tomato plantings.
6. Disinfection. Before planting, garden soil and soil for seedlings, containers for seedlings, planting material and garden tools are disinfected with antifungal drugs. All this carries fungal spores.
7. After cold, prolonged rains, plants must be sprayed with antifungal agents. The probability that the fungus has already infected the bushes under such conditions is 100%.
8. It is important to follow the feeding rules. Regularly add potassium and phosphorus to the soil. The amount of nitrogen fertilizers is minimized.

Useful tips from experienced summer residents

Experienced gardeners know several secrets of combating and preventing late blight. The list shows the most successful of them:

1. To avoid late blight infecting tomatoes, make sure that the soil around the tomatoes is only slightly moist.To maintain the optimal level of humidity in film shelters, several small holes are made in them.
2. To protect tomatoes from late blight, some gardeners spray them with a decoction of wormwood, dandelion or celandine. It is useful to add a few drops of iodine to this mixture. This preparation is not only used to spray the bushes, but also to water the soil. It has an antifungal effect and further enriches the soil.
3. It has been noticed that if you plant wheat, rye, basil or tobacco around the tomato beds and between the rows, the likelihood of them becoming infected with late blight will significantly decrease.

Reviews

Each vegetable grower chooses the best option for combating late blight.. Some of them leave useful information in reviews.

Inna, Moscow: “In our damp, cool climate, late blight is a common problem. I grow mainly cold-resistant varieties with immunity to fungi, but this does not always help. In my experience, it is useless to fight late blight once its symptoms have appeared on plants. I pay maximum attention to prevention. I plant tomatoes in the most sunny areas of the garden, using drip irrigation. After any precipitation or cold weather, I always spray the bushes with a solution of furatsilin or iodine.”.

Andrey, Belgorod: “I grow tomatoes only in open ground. Late blight usually affects them at the end of August. I make sure to follow the rules of care and spray the bushes with an ash solution and soap. If late blight appears during the ripening process, then I remove the unripe tomatoes, wash them with a weak solution of potassium permanganate, wipe them dry and leave them to dry in the sun. I cut off ripe fruits with spots and use them for preparing hot dishes.”.

Conclusion

Late blight is one of the most dangerous tomato diseases. In the later stages it is useless to fight it. However, there are effective methods of prevention. To do this, it is enough to follow the basic rules of care and avoid factors that contribute to the development of fungal infection.

Special medications will provide additional assistance in prevention. They are sold in stores and are easy to make yourself.