Powdery mildew on roses: control measures, what to do and what is the best treatment

In summer, most ornamental plants are exposed to fungal attack - powdery mildew; on roses and other flowers, the disease manifests itself as a white coating on the leaves. With further spread, the fungus affects the stems and buds. To protect plants, you should find out the cause of the development of the disease, as well as choose the most appropriate method of control.

Causes of disease

Powdery mildew is most pronounced on roses, the measures to combat the disease depend on the causes that provoked the fungal infection. Risk factors include:

• high humidity;
• over or under watering;
• high rainfall;
• high concentration of nitrogen in the soil;
• not getting enough sunlight;
• bushes too close to each other.

Infection of roses occurs when a favorable environment for the reproduction of the fungus is created, and this is, first of all, dampness. Therefore, for effective treatment and prevention of re-infection, care should be adjusted and comfortable conditions for the life of the plant should be provided.

Signs of disease damage

Recognizing an ailment is easy enough. It is not like other types of fungal infections. Its characteristic features include:

1. The appearance of plaque on the sheet plate. Young shoots are more susceptible to infection, on which the fungus settles in the form of a white powder.
2. Spots on the leaves. Reddish-purple spots and ulcers may appear on the leaf plate.
3. Pustules on the stem. The mycelium of the fungus is localized on the stem of the rose in the form of small growths. As the disease progresses, the pustules increase in area and density.
4. Plants stop growing.
5. Deformation and leaf fall.

First of all, leaves that are closer to the ground suffer. With the advanced form of the disease, plaque spreads to stems and buds. At the same time, the leaves are deformed and do not return their shape even after treatment with drugs.

White bloom covers the leaf plate, thereby creating an obstacle to photosynthesis. As a result, the plant does not receive the necessary nutrients and looks lifeless.

An equally common disease of roses, which is similar in appearance, is downy mildew.But there are some differences in its manifestation. Instead of a white bloom, red-brown or purple spots appear on young leaves, and mature leaves lighten and acquire a gray tint. At the same time, a dense layer similar to a cobweb is formed on the reverse side of the plate. Such symptoms are often associated with acid rain or sunburn. This disease should be treated with a solution of boric acid (5 grams per 5 liters of water).

Methods for treating powdery mildew on flowers

You can get rid of powdery mildew on roses with the help of special chemicals and folk remedies. It should be noted that the disease develops rapidly. Within two weeks, the plant can be completely covered with powdery mildew. Therefore, at the first sign of infection, it is necessary to take decontamination measures.

Chemicals

Fungicides are presented in a wide variety of contact and systemic agents.Contact fungicides are characterized by the destruction of the fungus in external contact with it. Systemic drugs penetrate the plant tissues and poison the juice, which has a detrimental effect on the pathogen.

Many growers use antibiotics such as streptomycin and penicillin to treat powdery mildew on roses. But experts do not consider this method effective, since antibiotics are not able to destroy the fungus. Their action is more effective in the fight against viruses.

Processing with chemicals implies a certain procedure:

1. Remove all affected parts of the stem from the rose. Remove fallen leaves from the ground.
2. Spraying should be done in calm weather, in the morning or in the evening.
3. Carefully treat the bush with the preparation, wetting the leaves, both from the upper and lower sides.
4. Indoor roses can be completely dipped in the prepared solution. You should also process the walls of the pot and pallet.
5. To improve the effect, systemic and contact fungicides should be alternated.
6. When spraying, be sure to work the ground around the bush.

This algorithm of actions is applicable to indoor roses. They are treated with the same drugs used for street bushes.

Fundazol

It is necessary to dilute the drug in the proportion of 5 grams of the product per 5 liters of water. When processing 1.5 liters of solution is consumed per 10 square meters of planting area. Fundazol is used at the first sign of damage to roses. Re-treatment should be carried out after 2 weeks.

Topaz

Systemic fungicide Topaz should be diluted at the rate of 1 milliliter of the drug per 2.5 liters of water. The solution consumption during processing is 1.5 liters per 10 square meters. Re-treatment of roses is carried out after 2 weeks.Topaz can also be used for preventive spraying.

Speed

Fungicide has both contact and systemic action. To prepare the solution, it is necessary to dilute 1 milliliter of the product in 5 liters of warm water. The distribution of the prepared solution occurs at the rate of 1 liter per 10 square meters of plantations. If necessary, the treatment should be repeated after 10-14 days. Suitable for treatment and prevention.

Important! To prevent the fungus from getting used to the drug, you should not use one fungicide more than three times in a row.

Folk remedies

In addition to chemical exposure, powdery mildew can be eliminated using folk remedies.

Whey solution

In the serum, diluted with water (1:10), add 10 drops of iodine. Roses are processed before noon. You can repeat the procedure after 10 days. In addition to disinfection, the serum helps to saturate the plant with micronutrients.

Soap and soda solution

Composition for spraying is made on the basis of baking soda and laundry soap. In 5 liters of water, dissolve 2 tablespoons of soda. Add 1 tablespoon of soap chips to the resulting composition. For prevention, the solution is used 1 time in 2 weeks. For the treatment of roses, the frequency of treatments is increased to 3 times a month.

You can also use soda ash. For the solution, you need to dilute 50 grams in 10 liters of water. Add 40 grams of laundry soap. Process no more than 2 times with an interval of 7 days.

Mustard solution

1 tablespoon of mustard powder dissolved in 5 liters of hot water. The solution is used after cooling, for surface spraying and watering.

Garlic infusion

To prepare a solution of 25 grams of chopped garlic, pour 1 liter of water. The composition should be infused during the day. Then it is filtered and used for its intended purpose.

Infusion of fresh manure

Fresh manure in the amount of 1/3 of a bucket is poured with 10 liters of water. Insist 3 days. The settled water is drained, and the concentrated precipitate is diluted in proportions 1:10.

Important! When using fresh manure, the proportions must be strictly observed. High concentration may cause burns.

Disease prevention

To prevent damage to roses by powdery mildew, you should follow the rules of agricultural technology.

To keep plants he althy, you need:

• stick to planting and trimming rules;
• check roses regularly;
• remove weeds and fallen leaves that become a source of disease;
• keep instruments sterile when pruning roses;
• control the dosage of nitrogen fertilizers;
• provide enough calcium and phosphorus for the plant;
• prophylactic treatment with fungicides;
• in autumn, carefully remove the leaves around the bush and dig up the soil.

For more likely protection, it is better to choose varieties of roses that are resistant to this fungal disease.

Powdery mildew resistant rose varieties

When buying roses, you should pay special attention to varieties that are resistant to powdery mildew. Thanks to the work of breeders, the choice of such roses is quite wide. The most popular among them:

• Purple Tiger;
• Cadillac;
• Hot chocolate;
• Rosoman Janon;
• Crocus Rose;
• Westminster;
• Gloria Day;
• Halle;
• Aphrodite.

These varieties do well in damp climates and are suitable for both home and greenhouse cultivation.

The appearance of powdery mildew on roses is most often the result of improper care and an unsuitable climate. Subject to preventive measures, the plant will delight its owner with long flowering and a he althy look.

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