Black powdery mildew on petunias how to fight. Powdery mildew control methods for petunias. Causes of the disease

Cascading and ampelous petunias grow faster than ordinary ones. If you solve the problem with additional lighting, a central shoot will quickly form, and then lateral ones, extending from it at a right angle. With a lack of light, side shoots grow worse and grow upwards. You can adjust the shape of the bush by changing the conditions of detention.

Experienced flower growers pinch the bushes during the growth period. They do this to slow down the development of the petunia. Breeders bred hybrid varieties, laying in them nice shape bush. When growing them, no special agrotechnical methods are used. They will be needed for seed propagation of ampelous petunias: the bush is formed by pinching, but still it will not be possible to turn it into an attractive-looking “ball”.

Important. How to prevent the growth of long lashes with ampelous petunias? It is necessary to prevent their flowering until a bush is formed. It takes 3 months or more.

• Cool damp air (day and night temperatures are around +20 degrees Celsius, and air humidity exceeds 70%).
• Excess nitrogen in the soil.
• Plantation density.
• Incorrect and irregular watering.

Sometimes petunia is affected by powdery mildew for other reasons. Infection does not occur due to non-compliance with the conditions of detention. The pest gets to it from neighboring crops, through water, or due to non-compliance with the precautions by the grower himself (pruning a non- and healthy plant with the same tool without treatment with an alcohol solution).

Diagnostics

For the first time, powdery mildew was discussed in the Russian Federation at the beginning of the 20th century.. Its causative agent is the fungus Sphaerotheca pannosa. It is easy to recognize an infected plant:

1. First, a whitish coating appears. It is noticeable on leaves and inflorescences.
2. After a few days, dew-like droplets appear on the stems and petals.

Experienced flower growers claim that the disease spreads from the lower leaves to the upper parts, including the buds. Without taking action, the plant will rot and die.

Attention. The best way to determine that powdery mildew is developing on a petunia is to carefully examine it when daylight.

To cure petunia, reconsider the conditions of detention:

Not all flower growers use drugs in the fight against powdery mildew, even knowing about their effectiveness. They believe in the benefits of folk methods. Petunia will recover if treated with a solution prepared from:

• 250 ml of milk;
• 750 ml of water;
• 1 tsp salt.

After mixing the above ingredients, pour it into a bottle and spray the petunia with a spray bottle.

Fungicide treatment algorithm

1. Changing the conditions of the plant. It is removed on a window sill immersed in the rays of the sun and the petunia is less often watered.
2. Remove infected areas, ie. buds, yellow and flabby leaves.
3. The top layer of soil is removed, and another, treated, is poured in its place.
4. Sprayed with fungicides, spreading them according to the manufacturer's instructions.
5. Make sure that the solution gets on all parts of the petunia.
6. IN severe cases dip the plant in a container with a solution.

Effective folk remedies

1. Soap solution with the addition of soda ash. To prepare it, take 20-25 grams of soda, 5 liters hot water and 5 grams of liquid (crushed laundry) soap. The mixture is cooled, and then the root section of the soil is sprayed with it. The frequency of the procedure is 2 times in 7-10 days. Do not spend it, seeing that the signs of powdery mildew have disappeared.
2. Weak solution of potassium permanganate. It is prepared by dissolving 2-3 grams of potassium permanganate in 10-13 liters of water. The processing frequency is once every five days. Number of procedures - 3.
3. A mixture of soap and ash. It is prepared from 1 kg wood ash and 10 liters of hot water. After mixing and infusion for 5-7 days, add another 5-10 grams of soap to it and process the bush. Before that, filter it. The ashes are not thrown away and poured into a pot for top dressing.

Advice. The folk remedies described above will not help if the grower noticed powdery mildew on petunias late.

Which of the "chemistry" is better to process?

Fungicides help in the fight against powdery mildew. They destroy the structure of the fungus, inhibiting its development in flower cells.

Fundazol

This fungicide has a wide range actions. It helps if diseases of leaves, buds and seeds are found on houseplants. The effectiveness of Fundazol is due to the presence of benomyl in the composition.

This substance penetrates the plant through the leaves and roots. After that, it is converted to carbendazim, which exhibits the best fungicide properties. After processing, Fundazol remains on the surface. Only partially it enters the plant. Because of this, the petunia is better protected from re-infection with powdery mildew.

Fundazol is sold in a 10-gram sachet. Price - 17 rubles. Breeding method - 1 gram / 1 tsp. water. After preliminary dissolution, bring the volume of the working solution to 1 liter. It is better to combine watering with spraying to remove the fungus. During the season, the plant is treated twice, if the first time it was not possible to destroy it.

Amistar extra

This combined fungicide is effective against many diseases, including powdery mildew. With his help:

• lengthen the growing season;
• increase the efficiency of water use;
• improve photoassimilation, nitrogen exchange;
• suppress the formation of ethylene.

Amistar extra is a drug that is produced in the form aqueous solution. In Russia, they sell it in liter canisters at a price of 1,500 rubles / 1 liter. The working solution is prepared by mixing the fungicide with water at a concentration of 1:10 or 1:4. After shaking, the plant is treated with it.

Speed

You can cure petunia if you buy a contact and systemic fungicide Speed at a price of 8300 rubles per 1 liter. The main active ingredient in it is difenoconazole.

For treatment, dilute 2 ml of the drug in 10 liters of water. It is not used for processing immediately after dilution. Twenty days later, the petunia is treated three times.

In the photo offered to your attention below, you can see what a petunia affected by powdery mildew looks like and how to deal with this disease at home:

Preventive measures

powdery mildew- a common disease. If you follow the recommendations from the list below, the petunia will never get sick.

• Growing petunias in a pot on a well-lit windowsill.
• Pots on the windowsill are placed at an impressive distance from each other to prevent the spread of fungal spores.
• If there is no living place left on the petunia, destroy it so as not to infect others.
• The plant is watered in the morning to increase its resistance to diseases.
• If you feed it, then only phosphorus and potash, and not nitrogen fertilizers.
• It is necessary to spray it with decoctions of horsetail or tansy from time to time.

Related videos

We suggest watching a video that talks about powdery mildew on petunias:

Conclusion

If you create the right conditions for growth and flowering, powdery mildew does not threaten petunias. Noticing a white coating, they urgently take action. Having missed the time, the plant may die, infecting others standing nearby on the windowsill.

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Constantine D.

I have powdery mildew in my garden. Petunias are especially affected. How to defeat the disease and not harm the flowers?

Petunias, due to their beauty, are very popular with gardeners. They are grown to decorate balconies, terraces and ground flower beds. Even with perfect flower bed care, the risk of powdery mildew cannot be completely ruled out. Let's try to figure out what kind of disease it is and how to deal with it.

Causes of the disease

Powdery mildew is a fungal disease, the pathogens of which live in the upper layers of the soil. With proper care, plants are rarely affected, but if the gardener makes at least one mistake, the disease will not keep you waiting. Remember that powdery mildew spores are activated under conditions:

• cool damp air (temperature 15-20°C, humidity 70-80%);
• excess nitrogen in the soil;
• thickening of plantings;
• irrigation failure.

In addition to pathogens living in the soil, the plant can be. Very often, the disease enters flower beds from neighboring trees or vegetable crops that were previously infected. Also, spores can enter the flower garden through water. And in some cases, the gardener himself, without noticing it, can become a carrier if, before working in the flower bed, he was engaged in pruning infected plants.

Important! Treat equipment and hands after working with infected plants, otherwise the risk of damaging healthy plants increases many times over.

Recognizing an infected plant is not so difficult. At an early stage, the disease looks like a whitish coating, this is especially noticeable on petunia inflorescences. At further development you can find small drops similar to dew on the petals and stems. The disease progresses from the lower leaves, but becomes noticeable only when it envelops the entire stem to the very buds. The consequence of the disease is rotting and death of the plant.

Powdery mildew spraying

To treat petunias for powdery mildew, follow the algorithm:

1. Remove all infected areas. This applies to buds, as well as yellowed and lost turgor leaves.
2. Remove the top layer of soil and replace it with treated soil.
3. Spray with a special preparation (foundazol, topaz, etc.).
4. Make sure the solution covers the entire plant.
5. For greater effect, you can dip the plant in a container with a prepared solution.

As is known, the most the best way the fight against powdery mildew is the observance of the rules of agricultural technology. Do not allow waterlogging of the soil and thickening of plantings. Proper care will not eliminate the possibility of infection, but will reduce the risk of disease by 90%.

Folk recipes for fighting

Folk remedies for controlling powdery mildew are effective in more for prevention, sometimes such methods are addressed to early stages infections. The most effective methods are:

1. A solution of soda ash with the addition of soap. To prepare the drug, you need 20-25 g of soda mixed with 5 g liquid soap and dissolve in 5 liters of hot water. Cool the resulting mixture to room temperature and spray the plant and root area of ​​the soil. Carry out the procedure 2 times, not more often than in 7-10 days.
2. A solution of potassium permanganate. It is necessary to dissolve 2-3 g of potassium permanganate in 10-13 liters of water. Apply 3 times with a break of 5 days.
3. Serum solution. Serum diluted with water in proportions of 1:10. Treat the whole plant with the resulting mixture. Due to the use of such a preparation, an organic film is formed on the leaves and stem, which prevents the flow of air to the mycelium. The plant receives additional nourishment during the treatment. It is important to carry out the procedure in dry weather.
4. A mixture of ash and soap. For cooking, you need to take 1 kg of wood ash and mix with 10 liters of hot water. Be sure to let it brew for 5-7 days, constantly stirring the substrate. On the last day, drain, leaving the sediment in the bucket. Add 5-10 g of soap and use a sprayer to treat the affected plant. You can carry out the procedure every day. Mix the ash sediment with water and use as a liquid top dressing.
5. Garlic infusion. Grind 25-30 g of garlic and pour a liter of water. Let sit for 24 hours and spray the petunias.
6. Mustard solution. 2 tbsp. l mustard powder is stirred into 10 l warm water. The resulting solution is settled for 3-5 hours and the plants are sprayed. Such a drug is used both as a treatment and for watering flowers.
7. copper solution. This tool is the most effective of all, prepared according to folk recipes. It has a special productivity due to the content of a natural fungicide - copper sulphate. For 300 ml of water, dilute 5 g of the drug. In another container, mix 50 g of soap with 5 liters of hot water. Stirring constantly, copper sulphate mixed with water is introduced into the soapy solution in a thin stream. The resulting liquid is used to treat all affected plants 3 times in 7-9 days.

With late detection (more than 5 days from the moment of infection), such methods are likely to not bring the desired results, in which case it's time to turn to "heavy artillery".

Treatment of the disease with chemicals

The most effective preparations used in the fight against powdery mildew are those containing a fungicide. It destroys the structure of the fungus and inhibits its development in plant cells.

by the most effective drugs are considered:

• Fundazol;
• Amistar extra;
• Speed;
• Topaz;
• Previkur.

Advice! For antifungal measures, Fitosporin can be used. Against a progressive disease, it is useless, but ideal for preventive work.

Remember that it is better to prevent a disease than to fight it. Prevent the progression of the disease and get rid of pathogens in the early stages. A trained gardener is not afraid of powdery mildew. He knows exactly how to deal with her.

How to deal with powdery mildew: video

Plants are often subjected to various diseases. One of them is the appearance of powdery mildew, white plaque on the leaves. Answering the question of how to deal with powdery mildew on petunias, it is worth saying that there are many methods of getting rid of. It is important to choose such a treatment method so as not to harm the petunia.

What is powdery mildew?

Before learning how to deal with powdery mildew on petunias, it is worth understanding what it is. Powdery mildew - rapidly developing fungal disease plants and shrubs. Plaque has White color and looks like dust or powdered sugar at first glance.

Over time, the plaque grows and captures not only the leaves, but also other parts of the plant. Old leaves gradually turn yellow and die, and new ones grow twisted and unhealthy. If you do not start treatment, the plant will die.

Advice! If a white coating is found on the leaves of a petunia, it is worthwhile to start treating the plant immediately.

If you increase the white bloom on petunias, you can see small sores on the leaves. The tissue of the plant is literally "eaten" by a fungal formation. Powdery mildew takes away all the nutrients from petunia cells and also interferes with the natural process of photosynthesis. It is necessary to get rid of such a raid as quickly as possible in order to prevent the death of the petunia.

Causes of Powdery Mildew

• the weather is cool and humid. Influence weather conditions perhaps when the petunia is growing outside or on a balcony. For indoor plants seasonality does not seem dangerous;
• concentrated in the soil a large number of nitrogen chemical compounds;
• the plant rarely thins out;
• irrigation is irregular. For example, when plants begin to water, without waiting for the soil to dry. Or vice versa, the earthen soil is completely dried out, and later it is poured. Such actions lead to a violation of the immunity of the plant.

In addition to external, third-party influence, the development of spores is possible if the petunia was poured with contaminated water, touched with hands after touching the infected petunia. It is also possible to transmit the disease through the air, from diseased plants and shrubs.

Petunia disease control

You can get rid of powdery mildew on petunias only with integrated approach to treatment. First of all, you need to properly care for the plant, namely:

• watering the petunia is necessary only after the complete drying of the soil, its upper layer;
• spraying during the fight against powdery mildew should be abandoned;
• the infected plant is taken out to a sunny place until it is completely cured;
• running plantings must be thinned out and cut off the dead leaves;
• during the disease it is not advisable to use nitrogen fertilizers.

Advice! For a speedy recovery of the plant, it is worth adhering to the rules of appropriate care.

It is necessary to correct the care process, otherwise it will not work for a short time to get rid of powdery mildew.

After adjusting the care, the algorithm of actions will be as follows:

1. Make cardinal pruning of the affected areas of the petunia. You need to cut off all the flower stalks and leaves. The more diseased plants are removed, the faster the healing process will go.
2. Fungal spores are found in top layer soil, it must be replaced with another.
3. Treat the petunia by spraying or watering with one of the medicines. It is necessary to spray as abundantly as possible, you can even dilute the medicine in a basin and dip the plant bush into the resulting mixture. You also need to process the pot and pallets.

Advice! In order for the petunia to get rid of a fungal disease, it is worth removing all damaged parts of the plant, as well as replacing the infected soil.

Mixtures and preparations for the treatment of petunia

such methods can only stop the development of the disease, but in order to completely eliminate the fungal infection, you will have to resort to the use of serious chemicals.

Here are a few recipes for treating white bloom on petunia leaves:

• 20 grams of soda ash and some liquid soap, dissolved in 5 liters of hot water. The resulting chilled solution is sprayed with petunia and soil.
• 30 grams of grated garlic are poured into 1 liter of water. The solution is infused for a day, filtered and after that they can be sprayed with petunia.
• for 2 tbsp. mustard powder - 10 liters of pre-boiled water. The cooled solution can be watered with a petunia, and also sprayed onto the plant.
• 100 grams of horsetail is poured with 1 liter of water and infused for a day. After that, the mixture is boiled for about two hours, then cooled and filtered. You can spray on the plant by diluting the infusion with water in a ratio of 1:5. You can spray regularly to prevent the occurrence of fungal infections.

If the situation has gone too far and folk methods petunia can not be saved, it is worth using chemicals. Fungicides in the fight against powdery mildew are very effective and can stop negative processes at the cellular level of the plant.

Depending on the preparation, it is recommended to spray the petunia no more than four times with an interval of 5-7 days. The most effective medicines are considered: Vitaroz, Acrobat MC, Fundazol, Forecast and Previkur.

Some advise such a drug as Fitosporin. However, it should be said that in the treatment of petunia, it will be ineffective and is only suitable as a prophylactic.

Petunia can be found in almost every garden. These bright flowers look very gentle and beautiful. They are grown not only for the garden, you can decorate them with a balcony or terrace. However, often powdery mildew attacks petunias. You need to know how this disease appears and how you can fight it.

Identifying a diseased plant is easy. At first, the disease manifests itself as a white coating, which is especially visible on the inflorescences. Then, as the disease progresses, droplets that look like dew can be seen on the stems and petals. The disease begins with the lower leaves, gradually spreading throughout the plant to the buds. As a result, the flower rots and dies completely.

The causative agents of this fungal disease are found in the upper layers of the earth. If the care of the plant is carried out correctly, then the disease rarely overtakes the flowers. However, it is worth losing sight of some moments of care, as powdery mildew can appear.

A variety of factors can activate powdery mildew spores:

• irregular watering of plants;
• cool damp air;
• an excess of nitrogen in the earth;
• very dense planting of flowers.

Powdery mildew can become infected not only because of pathogens located in the ground. Quite often, the lesion occurs from plants or trees that were previously infected with this disease. Sometimes pathogens can be in the water used for irrigation. The carrier of the disease can be the gardener himself. After working with plants infected with powdery mildew, it is necessary to process hands and garden tools.

Dealing with powdery mildew

If you find plants affected by powdery mildew, you must first get rid of all diseased buds and yellowed leaves. After removing the top layer of the earth, replacing it with a processed one. After that, you can spray the petunia with special preparations designed to combat powdery mildew (for example, fundazol). The optimal effect is helped to obtain products that contain a fungicide. The spray solution should cover the entire plant.

(reklama) It is possible to prevent infection of plants with powdery mildew if you follow all the rules of agricultural technology. It is necessary to ensure that the soil is not excessively waterlogged, and also not to plant flowers very densely in the flower bed. Compliance with these rules will help to significantly reduce the risk of this disease.

Folk recipes

Apply folk ways powdery mildew control is possible only on early stages the appearance of the disease. For more later dates they will no longer have a significant effect.

Most effective method the fight against powdery mildew will be a solution of potassium permanganate. In ten liters of water, two or three grams of potassium permanganate should be dissolved, after which the solution should be applied for three days, then taking a break for five days.

Another option is a solution based on soap and soda ash. It is necessary to mix five grams of liquid soap with twenty grams of soda, dissolve this mixture in five liters of hot water. Spray the petunia with this solution after it has cooled. The procedure should be carried out with an interval of a week.

You can use a mixture of ash and soap to combat powdery mildew. Add a kilogram of wood ash to ten liters of hot water. Infuse this mixture for a week, not forgetting to stir it periodically. On the last day, drain the water, leaving sediment at the bottom. Add ten grams of soap to it, mix with water. Spray the plants with the solution daily.

A beautiful flowering petunia can be attacked dangerous disease- powdery mildew, which is rapidly spreading through the flower, and if it is inactive, it will be doomed to death. You can fight it with chemicals and folk remedies. Both of them have a visible result and contribute to the speedy recovery of the petunia.

The causative agent of the disease is a fungal microorganism. It lives in the upper layer of the soil, survives frost well and does not die. If the care of the petunias is carried out correctly, then the risk of infection with powdery mildew is minimal. For favorable conditions for the development of the fungus, you need:

• an excess of nitrogen-containing compounds in the soil;
• cool temperature (15-20 degrees);
• too dense planting;
• improper watering;
• excessive moisture.

The cause of infection may be a nearby infected bush or flower. Dew passes to a healthy culture and affects it in a matter of days.

Signs of appearance

The most basic sign is the appearance of a white coating on the leaves and buds of petunias. Then, drops similar to dew form on the inflorescences and shoots. Last stage there is a complete rotting of the stem, the flower itself and the root system. As a result, the plant dies.

At the time of infection, the fungus does not manifest itself in any way. It is even impossible to understand that a petunia has become infected with powdery mildew in the first days. The first signs may appear after 2 weeks. At first, the flowers may seem sluggish, the stem loses its elasticity, and the inflorescences fall off.

What to do if flowers and leaves are infected

If a raid still appears, you should not panic - the petunia can be saved. All infected shoots and inflorescences are cut with scissors or cut with a knife - they can no longer be cured. the main task- prevent the spread of the disease to a healthy part of the flower. To do this, you can use chemical and folk methods, as well as some methods of agricultural cultivation.

Chemicals

Fungal diseases are treated with special preparations - fungicides. They block the spread of the infection, as a result of which the fungus dies. There are many fungicides. You can treat petunia with Topaz, Fundazol, Fitosporin.

These drugs are used in accordance with the instructions that the manufacturer indicates on the package. As a rule, the whole plant is covered with a diluted mixture, leaving the drug to act. Be sure to re-process after 5-7 days, to consolidate the result.

Important! Part of the solution can be used to irrigate the earth, as it may contain fungus.

Folk remedies

There are remedies that have been proven over the years that can be prepared from simple ingredients at hand. In the fight against powdery mildew, they show great efficiency, do not have a toxic effect on the flower itself. Here is an example of preparing one solution:

• 1 tbsp baking soda;
• 1 tsp liquid soap;
• 3 liters of warm water.

Mix all the ingredients, and then apply the mixture on the shoots, leaves with a spray bottle. The frequency of use of the solution should not exceed 1 time in 7-10 days.

For the treatment of petunias with powdery mildew, potassium permanganate is sometimes used. Being a strong oxidizing agent, potassium permanganate instantly kills pathogenic microflora, as a result, the plant recovers in a few days. Dilute 3-4 crystals of potassium permanganate in 3 liters clean water. Should be a solution Pink colour. Sprayed with petunias and watered the basal plot of land 1 time in 5 days for 2-3 weeks.

Garlic infusion will help defeat a fungal disease. Prepare a mixture consisting of:

• 20-25 g of garlic mass, chopped on a grater or garlic crusher;
• liter of water.

Infuse the mixture for a day, and then water the soil near the roots and spray the flower for 14-20 days with a period of 1 time in 5-7 days.

A mixture of water and mustard prevents the spread of fungus in the flower, so it is often used to combat dew. Dilute 1 tablespoon of mustard powder in 3 liters of water and irrigate with petunias from top to bottom. 2-3 treatments are enough for the flower to survive and not get sick.

Agricultural practices

Since powdery mildew is often provoked by excess moisture, the frequency of watering petunias must be reduced. The earth should be allowed to dry well and not watered for a week or even more. Spraying flowers with water is also not necessary.

Attention! For irrigation, water with low hardness is used - it can be filtrate or settled water.

After watering, the soil in the pot is loosened a little so that the water does not stagnate and quickly passes deep into the soil. Such simple tips help the flower recover faster, but must be accompanied by mandatory treatment with a fungicide or other agent.

Prevention

To avoid trouble, you need to take measures in advance - to carry out timely prevention. To do this, treat petunias 2 times in spring and early summer. You can use blue vitriol, beloved by all summer residents. Dilute a 3% solution of the substance and water the soil and plants with it. In addition to treatment with a solution, when growing petunias, you need:

• respect the planting distance between the flowers. It is necessary to retreat from a neighboring flower, at least 7-10 centimeters;
• transplant only in safe ground. Before planting, the earth is watered with potassium permanganate, Fitosporin;
• work only with clean tools. Shovels or choppers, rakes are kept in boiling water for a couple of minutes before work to get rid of possible carriers;
• observe the frequency of watering, timely remove old yellow leaves and already faded flowers.

Powdery mildew can and should be fought, the sooner treatment measures are taken, the more likely it is to save the flower. Even after an illness, the petunia quickly rehabilitates, there are no traces of the disease on the flowers and leaves, the plant continues to decorate the garden.