Black spot on roses than to treat. How to treat the disease

Any gardener dreams of a beautiful, fragrant and healthy flower garden. Lush and bright roses are especially pleasing to the eye. But the cultivation of these capricious flowers cannot be imagined without problems. Often various diseases, viruses, fungi and insects spoil appearance and even destroy the royal flowers.

Symptoms of the disease

The gardener may not notice the infection of the rose immediately, but if the first signs have already appeared, then the development of the fungus will go very quickly.

It is important to take urgent action. Black spots on rose leaves do not look too aesthetically pleasing. How to treat the fungus will be described below.

The disease begins with the appearance of brown spots with yellow edges on the leaves. Over time, the leaves turn completely yellow and fall off. The fungus also passes to the stem, which turns yellow, darkens and fades. As a result, the rose bush ceases to bloom and takes on an unaesthetic appearance.

What can a florist do to prevent roses from becoming infected?

Black spots on rose leaves: what to do?

What other means can cure black spot?

In specialized stores, you can buy products that contain triazole and mancozeb. In order to obtain an excellent and long-term result, these funds are used in turn. First, within a week, roses are treated with mancozeb products (for example, Profit). Then comes the time for preparations with triazole ("Topaz", "Skor"). Bushes are also processed with this liquid for a week (every day).

Roses are processed in the evening. In the morning, this cannot be done because of the rose on the leaves, and in the afternoon - because of the possible heat and direct sunlight falling on the leaves of roses treated with means.

Preventive measures against black spot

It is very difficult to cure infected rose bushes, so it is better to take preventive measures to prevent this fungus. You need to start the fight with the right purchase of seedlings. Buy roses in trusted places, seedlings must have all the necessary certificates and documents. Pay attention to the variety of roses - many of them are resistant to the appearance of black spot, a kind of immunity.

When the purchase is made, think about choosing a place for planting seedlings. This is very important condition, after all, a rose is a whimsical flower. You should not plant roses in the place where these flowers (or any other diseases similar to roses) were already planted less than 5 years ago. Properly care for the flower garden and constantly inspect them for the appearance of something strange. If you see that rose leaves are covered with black spots, start treatment immediately! A rose can quickly die from a harmful fungus.

Other types of rose spot

The queen of flowers can suffer not only from black spot. How to recognize other types of disease?

• Cercosporosis - brown spotting. With this type of flower damage, its leaves cover brown spots. Their size is approximately three millimeters; around a brown spot, you can usually see a dirty red rim or a greenish coating.
• Septoria - affects roses with spots of white or dark brown. Points of accumulation of fungi are clearly visible on the spots.
• Sphaceloma are black or dark red small spots. Around each speck there is a red border, which gradually brightens.
• Perenosporosis are large brown spots. Their shape may be different, but the stains dry quickly. Distinctive feature this type of spotting - grayish plaque on the wrong side of the rose leaf.

Measures to combat these types of spotting are almost the same as the treatment of black spots on rose leaves. Constant checking of the bushes and preventive spraying will help protect the plants.

If you see black spots on the leaves of a rose, do not hesitate! Otherwise, the plant can simply throw all the buds to the ground. If the fungus is started, then the rose may die altogether. Don't forget about timely watering, pruning, mulching, loosening the soil and weeding. The rosary needs constant careful care, only then the flowers will delight the gardener's gaze.

Darken the beauty of flowering rose bushes capable of the appearance of ugly spots on the leaves. The spots can be brown, white, yellow, red, or rusty in color, and in all cases indicate problems with the health of the plant.

Black spot - fungal disease, the symptoms of which most often appear in summer period, not only significantly reduces the decorative effect of the bushes, but can also interrupt the flowering of roses.

Black spot in roses is caused by the fungus Marssonina rosae. The causative agent is spread by spores and is activated in conditions of high humidity in warm weather. Most favorable time for the development of the fungus is spring. The disease rarely appears in dry and hot summers.

First of all, bushes growing in lowland areas or surrounded by dense thickets of plants in a flower garden are susceptible to the disease, since these factors prevent the normal evaporation of moisture after precipitation and irrigation. The development of fungi is also facilitated by: lack of lighting or nutrients in roses, potassium deficiency, excess nitrogen, heavy and acidic soils are especially critical.

Symptoms and course of the disease

The disease does not manifest itself immediately, the first signs of damage appear a month after the active development of the fungus. The exception is warm and humid summers, at a temperature of about 30 ° C, the disease becomes noticeable after 10 days. On average, black spot on rose bushes is most likely to be found by mid-summer.

The lesion spreads from the bottom to the top of the bush. On the leaves and shoots appear dark brown spots, framed by a yellow border. As the disease progresses, other symptoms appear:

• the spots turn black and increase in size;
• twisting and yellowing of leaves is observed;
• fall of foliage from the bushes;
• slowing down and stopping the growth of shoots;
• poor formation of flowers, up to the cessation of flowering.

Attention!

The spores of the fungus overwinter safely in the ground, which makes it likely reappearance illness next season.

black spot treatment

The fight against black spot comes down to pruning the affected parts from the bush, treating the plants with antifungal agents and preventive measures that also inhibit the development of the fungus.

Timely spraying of roses folk remedies, as a rule, give a positive result, while the use of chemical fungicides is recommended in the later stages of the disease. It is worth considering that after the appearance of the first symptoms, the disease begins to develop very quickly.

The most powerful folk remedies:

Advice!

In autumn, when pruning bushes, affected shoots, regardless of the degree of damage, should be cut to the level of the second or third bud.

Prevention

Black spot prevention measures include:

• providing roses suitable conditions for growth;
• compliance with annual sanitary measures;
• preventive treatments in case of risk of disease.

Growing conditions

Prevention of black spot in roses begins with the choice of a place for planting bushes and planning a flower garden.

Culture requires:

1. The sun. For roses, sunny places should be allocated where the plants can receive enough light during the day. This will also benefit flowering and the general condition of the bushes.
2. Weak soil. When planting on soils with hyperacidity it is necessary to carry out the liming procedure - add 250-500 g dolomite flour or 150-250 g of lime.
3. Space. Maintaining a distance between the bushes prevents the rapid spread of the disease. Also, do not surround the bushes with a dense wall of other plants - the fungus often appears where there are obstacles to free air circulation.
4. Good food. Roses need to be fed during the growing season, during and after flowering. It is necessary to provide plants with phosphorus, potassium, do not forget about feeding with micronutrient fertilizers, but show reasonable moderation in nitrogen nutrition.
5. "Crop rotation". It is advisable not to plant bushes in places where roses have already grown. Planting can be done only 5 years after the cultivation of other crops on this site.

Landing Hygiene

In spring and autumn, it is necessary to carry out a number of sanitary measures aimed at reducing the risk of diseases in roses.

1. It is recommended to remove dry and damaged branches twice a year - when preparing the bushes for wintering and after the release of roses from shelters in the spring. If necessary, thinning crown pruning should also be done.
2. In autumn, before placing the roses under cover, you need to clear the bushes of the remaining foliage.
3. Since the spores of many fungi, including the black spot pathogen, hibernate in the ground, on the eve of sheltering the bushes and immediately after removing the protection in the spring, the soil under the roses should be treated with a 0.01% solution of copper sulfate. It is recommended to alternate this remedy with a solution of ferrous sulfate.
4. In autumn, you can also treat the bushes with Bordeaux liquid or a solution of copper sulphate at a concentration of 3%.
5. In the spring, it is worthwhile to spray the roses once with the preparations "Skor", "Profit", "Ridomil Gold" or "Strobi" during the period when the leaves appear. An alternative to this may be two sprayings with biological agents, for example, with Fitosporin-M, performed with a week break.
6. Throughout the season, it is necessary to remove weeds from the flower garden that thicken the planting.

On a note!

Bush processing

If spring or summer turned out to be rainy and warm, you should play it safe by taking additional measures against fungal diseases. It is recommended to carry out regular weekly treatments throughout the season:

1. Infusion of tobacco. A bucket of water requires 500 g of dried and finely chopped tobacco leaves. Raw materials are poured with boiling water and left for 5 days. Before use, the infusion must be filtered.
2. Garlic infusion. Take 200 g of chopped garlic heads and pour a liter warm water. After 5 days of infusion, the solution is filtered and 1/2 cup is added to a bucket of water.
3. Wood ash. Directly during the rainy season, the ashes should be scattered in the near-trunk circle of rose bushes.

resistant varieties

The least resistance to black spot is shown by varieties of such groups as tea, polyanthus and climbing roses. Planting them should be avoided if conditions favor the appearance of the fungus. And the most resistant to damage by spotting are varieties of roses with glossy leaves - their dense skin is "too tough" for the fungus.

Among the most resistant varieties are:

• "Grande Amore";
• "Baronesse";
• Quadra;
• "La Perla";
• "Leonardo de Vinci";
• "Memory";
• "Sebastian Kneipp";
• "Nostalgia";
• Resonance.

The most important thing in the fight against black spot is to provide roses with quality care, since the fungus primarily attacks weak and depleted plants. If, for some reason, roses are at risk, it is necessary, without waiting for the appearance of diseases, to take measures to restore their resistance to adverse factors. To do this, enter special treatment fertilizing (enhanced nutrition with potassium), watering the bushes with growth stimulants and using drugs to strengthen the immunity of roses.

We will tell you about rose diseases and how to deal with them.

Black spotted roses

The causative agent of black spot is the fungus Marssonina rosae, which covers the leaves and stems of roses with brown and black spots, which can be one or more, and they often come together.

The leaves affected by black spot begin to turn yellow and fall off, so if the plant is left untreated, then after 2-3 seasons it can die.

Prevention. Proper care, timely top dressing, pruning, shelter for the winter will help protect roses not only from black spot, but also from many other diseases. Here are some preventative tips:

❧ buy seedlings only from trusted suppliers;

❧ during autumn cleaning, it is important to collect and burn all the leaves that have fallen from roses, as well as cut and destroy the affected shoots;

❧ it is necessary to fertilize regularly, in reasonable quantities, otherwise the stems of roses will become thick and flowers will not form;

➣ Breeders breed varieties of roses that are resistant to black spot, first of all, these are varieties of the floribunda species.

Control measures. The onset of the disease occurs at the end of spring. After the snow melts and the soil warms up, black spot spores begin to infect the plant. If the rose is not treated, then in the fall it will throw off the infected leaves, and in the spring the infection will occur again.

If the rose is affected by black spot, at the end of spring it needs to be sprayed with fungicides - preparations containing zinc and mancozeb. Repeated spraying is carried out after 14 days. In the fight against black spotting, drugs such as Topaz and Ridomil Gold have proven themselves well.

Sometimes spraying is carried out even if the plant is not infected with the disease, in order to prevent possible damage to the seedlings. For this purpose, they are sprayed at the end of spring, when it is already warm. Repeated spraying should be carried out if the plant began to show signs of infection.

rose rust

Very often, the cause of most diseases of roses is the vital activity of insect pests. By infecting the plant, they weaken it, from which the rose becomes susceptible to various fungal diseases.

One such disease is rose rust, which is caused by the fungus Phragmidium mucronatum. It infects the buds, stems and leaves of roses, resulting in a growth on the stems and upper parts of the leaves, and pustules similar to rust spots form on the lower parts. From these pustules, spores of the fungus are released, which infect healthy parts of the rose and neighboring bushes. As a result of the disease, the leaves begin to turn pale and fall off, the plant becomes weak and, without treatment, can die in 1-2 seasons.

In the first stage of the disease, which occurs in mid-spring after the buds begin to open, outgrowths form. During this period, the development of the disease is most active, since the humidity of the air is increased. Then it infects the leaves, on which yellow spots gradually covering the entire sheet plate. The shoots of roses become thick, cracks appear on them.

Toward the end of summer, the growths become dark and remain on the plant all winter. On the fallen leaves, rust spores also remain, which again infect the bushes in the spring.

In early spring, the disease also develops actively, while in hot and dry weather in summer its development slows down.

Prevention. To prevent rose rust, it is necessary to remove fallen leaves in time and do this not only during autumn harvesting, but also in summer, so that spores do not infect healthy parts of plants.

Rose hips are more prone to rust, therefore, if it is present in the garden, it is necessary to monitor the appearance of signs of the disease. Rust fungus spores are carried by the wind, so you need to destroy the affected parts of the plants in time.

Control measures. If the roses show signs of disease, it is necessary to remove and burn the affected parts. It is also recommended to thin out rose bushes, which will allow air to circulate freely and prevent high humidity. You can spray against the disease with fungicides, re-spraying is carried out 1-1.5 weeks after the 1st. Against the rust of roses, preparations such as Abiga-peak, Topaz, as well as blue vitriol and Bordeaux liquid.

powdery mildew

Powdery mildew is one of the most common diseases, and not only roses. Its causative agent is the fungus Sphaerotheca pannosa, which has a huge number of varieties, because this disease affects both roses and other flowers, as well as berries, fruit and vegetable plants.

On powdery mildew-affected roses, specific powdery spots of white or gray color. As a rule, stems, leaves and buds are the first to suffer from the disease.

Powdery mildew appears in both wet and dry weather. However best conditions for its Development - warm weather and shade. At the same time, the fungus does not tolerate high temperatures and direct sunlight, which turn out to be fatal for it.

If you do not start fighting powdery mildew in a timely manner, then it will cause serious damage to the plant, as a result of which the rose will grow and develop worse, and its appearance will worsen.

All types of powdery mildew fungus can only survive on a living plant. On roses, the fungus lives on buds and stems, in the winter it can go to some weeds, and in the spring it will spread again from them to roses. To powdery mildew developed on roses, requires an air temperature of 20-25 ° C and a humidity of 40-90%. If the plant is in the shade, then this can also affect the development of the fungus. From the onset of the development of the disease to the appearance of new spores, it usually takes about 2-3 days, and if the weather is unstable, then this period can last 1-1.5 weeks.

Prevention. To avoid powdery mildew, it is quite enough to carry out prevention and control the correct development of roses. This also facilitates the fight against powdery mildew, if the disease still affects the plants.

Also great importance has distance between rose bushes. If they have access fresh air, this prevents the appearance of powdery mildew.

❧ beautiful woman from Indian legends, the goddess of beauty Lakshmi was born from a blossoming rose bud.

It develops rapidly on plants growing on soils rich in nitrogen, so it is recommended to apply mineral fertilizers in strictly specified quantities. And it is better to give preference to organic.

Control measures. It is necessary to regularly remove and destroy the parts of plants affected by the disease, and in this way it is possible not only to fight powdery mildew, but also to increase the flow of fresh air to all parts of the plants. If a rose bush is severely affected by a disease, then it must be dug up and burned - it is better to sacrifice one plant in order to save all the others.

After the destruction of parts of roses affected by powdery mildew, it is recommended to spray. For this purpose, you can use drugs such as Skor, Fitosporin, Baktofit, Topaz. If the first signs of powdery mildew appear on the roses, you need to spray the plants with fungicides containing sulfur, and after 1-2 weeks, repeat the spraying if necessary. A large amount of sulfur is found in garlic, so you need to plant it next to rose bushes to prevent the development of powdery mildew. You can also create powdery mildew solutions at home using squeezed garlic juice. If roses are sprayed in time, it is easy to prevent the development of powdery mildew, as well as to simplify the fight against it if the fungus still infects the plants.

In addition to sulfur, the solution helps fight powdery mildew. baking soda to be sprayed once a week. Soda helps to increase the pH of the surface of the rose leaf, which prevents the development of powdered spores on it. When treating roses with preparations with sulfur or baking soda, you need to make sure that both the top and Bottom part leaves.

To prepare a solution of baking soda at home 1 tsp. soda is diluted in 1 liter of water, and then a few drops are added liquid soap. Before spraying roses with this solution, you need to make sure that the plant will tolerate such a procedure well. Why should you apply the solution to several leaves and observe them for a couple of days. If there are no changes, you can safely spray the roses.

Anthracnose roses

Anthracnose is caused by the fungus Sphaceloma gosarum. This disease is still little studied, but it poses a serious danger to roses, especially in cool and humid spring conditions. Moreover, anthracnose can damage both wild and cultivars roses.

With anthracnose, small black spots appear on the leaves, which make it difficult to recognize the disease, since the symptoms are similar to black spot. As the disease progresses, the nature of the spots changes. Young spots are mostly red in color, sometimes they can be purple or brown. They form on the upper side of the leaves and can be about 50 mm in diameter. The center of the spots becomes white or gray, sometimes holes form in it.

The disease develops on the leaves and stems of roses. The small black dots in the center of the spots are spores of the fungus that causes anthracnose. As the disease progresses, holes form in place of the spots, nutrients unable to move normally through the parts of the rose, which leads to a weakening of the plant. A rose affected by anthracnose develops poorly in the future, the leaves are deformed, and the plant dies. The active development of the disease occurs in the spring, especially in the rainy and cool period, when there is an excess amount of moisture.

Prevention. In order to succeed in the fight against anthracnose, it is necessary to take into account life cycle fungus and how it tolerates winter. It remains in winter on infected stems and leaves of roses, and with the onset of the first warm spring, new spores begin to develop from old wounds.

Anthracnose spores are carried to healthy plant parts by wind and rain spray. Wet and cool weather contributes to the active development of the disease.

To avoid damage to roses by anthracnose, it is recommended to cut and destroy the damaged parts, stems and leaves. These measures will help prevent the reproduction of spores and contribute to the preservation of the plant. In autumn, it is required to cut off all damaged parts of the bushes, remove and burn the fallen leaves, on which anthracnose spores can remain. Then in the spring the likelihood of re-infection of plants will decrease.

Control measures. If a timely sample, spring work and autumn cleaning did not help, you need to deal with anthracnose in the same ways as with black spot.

Downy mildew on roses

The causative agent is the fungus Pseudoperonospora sparsa. This disease is dangerous for almost all plants, and most gardeners have to deal with it. She also infects roses. The disease is similar to chemical burns, so it is not always recognizable. In the spring, when there is especially a lot of moisture, the first symptoms of the disease appear, which are expressed in small reddish-brown spots covering the leaves and shoots.

The leaves acquire a creamy white color, stop developing, over time they become deformed and fall off. The stems begin to crack, the flower petals lose their natural color, do not develop and fall off. As a rule, downy mildew is found already at the stage of leaf fall. If you do not take action, then the roses may die. The disease is especially dangerous in wet weather; in dry and hot weather, the development of the disease stops.

Prevention. Downy mildew appears from exposure to waterlogged soil and cold, moist air. If the seedlings are stored in the basement, then their stems should not be often moistened, because this can kill the plant. To prevent the development of the disease, it is necessary to provide access to fresh air to the seedlings. As a preventive measure during the growing season, potassium and phosphate fertilizers so that the roses have resistance to downy mildew.

❧ During the Renaissance, dew on rose petals was considered a symbol of the goddess Venus, as it had incredible beauty and captivating aroma, and rose thorns symbolized wounds and suffering from love.

Control measures. If symptoms of the disease are found on roses, it is necessary to cut and burn the affected parts of the plants. Then they should be sprayed with fungicides, such as Bordeaux mixture, "Benomyl", "Kuproksat", "Topaz". Fallen leaves and petals affected by downy mildew must be collected and burned. The disease perfectly tolerates wintering on the fallen affected areas of the leaves, so you need to get rid of them.

gray mold on roses

The causative agent of the disease is the fungus Botrytis. The causes of gray mold are low temperature and excess moisture. Light spots form on the plant, fluffy rot develops.

In spring, the risk of gray mold infection of roses is especially high, since the weather has not yet arrived and it often rains. Also, the plant is able to get gray mold after wintering in the basement. There are many varieties of gray mold fungus. It is necessary to start treating the rose in time so that the disease does not spread to other plants in the garden.

Prevention. In the room where seedlings are stored or roses overwinter, it is necessary to reduce humidity and provide fresh air. At the site on time spring pruning bushes so that air circulates freely between the stems.

Control measures. If gray mold is found on roses, immediately remove and burn the affected parts of the bushes and spray them with sulfur-based fungicides (Benazol, Benomyl, Benorad, Fundazol). Re-spraying can be done after 2 weeks. It is also recommended to make sanitary pruning of roses. To prevent the plants from getting sick again the next year, you need to remove and burn the fallen leaves.

Aphids on roses

Aphids are one of the most common garden pests. These are small wingless insects with soft green bodies.

Adults develop wings. Aphids live in colonies, so a large invasion of this insect is immediately noticeable on roses. Aphids can quickly move to neighboring plants, affecting the entire garden. Hot spring days are especially dangerous around mid-April. Aphid larvae, wintering in the bark of plants and in fallen leaves, move to young shoots. After 10-14 days, the number of aphids increases significantly. At the same time, roses are also affected by pests such as spider mite and pink cicada.

Not a large number of aphids on roses will not cause much trouble, but this pest reproduces very quickly, so control over its numbers is necessary, otherwise the roses can die. It is required to deal with aphids after the appearance of the first individuals.

Each female is able to lay several hundred eggs, from which new pests emerge. First of all, the aphid infects the shoots and buds, sucking the juice out of them, as a result of which the leaves are deformed and die, the buds do not open. The aphid itself rarely leads to the death of the plant, but its numerous colonies discolor the leaves, make the bushes unsightly, by autumn the roses are very weak, which makes them poorly tolerate wintering. Also, as a result of the weakening of the plant, it is more vulnerable to the effects of disease-causing fungi.

Aphids settle on roses and secrete a sticky liquid that coats the stems and leaves of roses. Ants feed on this sweetish liquid. If a large number of ants are seen on roses, then they are most likely affected by aphids. Ants protect aphids from their natural enemies. The absence of ants affects roses affected by aphids not the most in the best way, since there is no one to eat the nectar and, as a result, all rose bushes may be covered with aphid products. This leads to an increased risk of black mold. The appearance of roses also suffers.

Prevention. Prevention, as well as the fight against aphids, is desirable to carry out without the use of chemicals. It would be even better to abandon them altogether. Such natural enemies of aphids as insects and birds will cope with the task more successfully than any chemistry. If you use toxic agents, then you can kill bugs, spiders and flies that feed on aphids. For example, wasps and ladybugs they love aphids. The latter are generally capable of destroying about 250 aphids per day. The use of chemicals is able to scare away birds and lizards from roses, which also feed on aphids.

Control measures. The aphid has a very delicate and soft body, so you can get rid of it by simply running a soft cloth over the affected areas. Thus, it is easy to control the number of insects. You should also not feed roses for some time if aphids are seen on them, as a result, young shoots will stop developing, and therefore there will be no additional food source for aphids.

Instead of chemicals, you can spray roses with a jet of water from a hose. When watering roses, aphids will be destroyed by splashes of water, and the remaining individuals will be eaten by birds or insects. Watering roses in this way is recommended for a week every other day, which will help to significantly reduce the number of aphids and restrain their spread throughout the site.

If water does not help, and there are few aphid-eating insects in the garden, then a soapy or kerosene solution can be used for spraying.

For cooking soap solution against aphids, it is recommended to dissolve 200-300 g of liquid or laundry soap in 10 liters of hot water. The solution must cool down hot water can harm bushes. This method safe both for the roses themselves and for the environment.

You can also prepare a kerosene emulsion at home. Dissolve 100 g of laundry soap in 100 ml of water, bring to a boil, heat 200 ml of kerosene and add to soapy water. The resulting emulsion must be diluted in 10 liters of water and sprayed with this solution. It is recommended to process several times a day for about a week. After spraying with kerosene, it is recommended to wash the roses clean water to let the leaves breathe.

The body of aphids is so soft that when fighting these insects, you can get by with slightly toxic drugs that will be fatal to them. If, however, highly toxic agents are used, then it is easy to destroy or scare away the natural enemies of aphids, and therefore, after a while, an outbreak of aphid reproduction can occur, because there will be no one to fight it.

This time we invite you to learn about unconventional ways protection against well-known diseases typical of many diseases, as well as highly specialized diseases of roses.

The occurrence of diseases in roses is promoted by unfavorable weather(for example, wet summer or a long dry and hot period), poor lighting, dense plantings and poor ventilation of the rose garden, mechanical damage to plants, etc.

In general, infectious diseases in roses can be caused by pathogenic fungi, viruses and bacteria.

Infectious burn, or stem cancer of roses.

In the spring, brown spots with a depressed surface and thickening edges may appear on last year's rose shoots. The spots dry up, the bark of the shoot cracks, the shoots of the rose die off above the affected area - these are signs of an infectious burn of roses. An indispensable condition for avoiding an infectious burn is the shelter of roses for the winter in dry weather. In the autumn, before sheltering the rose, you need to cut out the unripe shoots and burn them, tear off the leaves from the bush.

To prevent stem cancer of roses, you must:

• Avoid over-application under plants nitrogen fertilizers;
• fertilize roses potash fertilizers to strengthen the tissues of the shoots;
• cover roses in a timely manner and air the bushes during winter thaws;
• timely remove shelters of roses in the spring;
• cut and destroy shoots affected by cancer.

Powdery mildew on roses

This is one of the most dangerous and common infectious diseases of roses. First, a white cobweb or powdery coating appears on roses affected by powdery mildew. Then the mycelium thickens, the plaque becomes brownish-gray. The spores of the fungus are formed throughout the summer and are carried by the wind to long distances. The leaves of roses with powdery mildew curl, the affected areas of the shoots die off. Such roses weaken and may die during wintering.

The development of the disease is facilitated by excessive fertilization of roses with nitrogen, calcium deficiency in the soil, lack or excess of moisture, thickened plantings. Roses with leathery or glossy leaves are resistant to powdery mildew.

In the fight against powdery mildew, you need to combine correct agricultural technique(strictly monitor the diet of roses, avoid excess nitrogen fertilizers before budding, feed roses during this period with phosphorus-potassium fertilizers; to increase the size of flowers, it is advisable to feed with Baikal EM1 and Humistar) using fungicides (antifungal drugs) at the first signs of the disease.

Folk remedies for prevention. To prevent the introduction of infection into the garden, purchased roses should be dipped "head over" (for 15-20 minutes) in a solution of copper sulfate (1%) and then regularly sprayed with one of the preparations:

Infusion of mullein (1:10);

Five-day infusion of ash (1 cup per 10 liters of water);

Potassium permanganate solution (2.5 g per 10 liters of water);

A solution of soda ash with soap (40-50 g of soda and 40 g of soap per 10 liters of water).

Modern means of prevention. Increasing resistance is facilitated by the introduction of microfertilizers, for example, Aquadon-micro, the use of immunomodulators, such as immunocytophyte, Narcissus. The destruction of cells of harmful fungi is facilitated by the enzymes contained in Humistar. Plants are strengthened by feeding with Baikal EM1 and organic fertilizers based on it.

When powdery mildew appears on roses, it is necessary to immediately treat the affected plants with one of such fungicides as Fitosporin (biol.), Alirin-B (biol.), Bordeaux mixture (1%) (chemical), or a solution of copper oxychloride (0.4 %), or Copper-soap solution (for 10 liters of water 20-30 g of copper sulfate and 200-300 g of soap). Where possible, for environmental reasons and for the sake of conservation own health try to use biopreparations. Prolonged use of copper-containing fungicides can lead to excessive accumulation in the soil, that is, in amounts harmful to plants.

Leaf spots of roses.

At the beginning of summer, especially cool and rainy, brown spots may appear on the leaves of roses, which gradually merge and turn black. On black spots, swellings of a rounded or oblong shape appear. The affected leaves of roses turn yellow and fall off, the bushes become bare - the immunity of roses decreases, the plants weaken and grow and bloom poorly in the future.

Except black spot leaves, brown spotting (brown spots with a black border) and white spotting (white spots with a dark red rim) can occur on the leaves of roses - these diseases provoke heat and air humidity.

Spotted, fallen leaves of roses must be collected and burned, and then the same measures should be taken as against powdery mildew.

Mulching the soil in the rose garden with cut grass keeps the spread of spotting on rose leaves. Roses with glossy leaves are less susceptible to spotting.

Dark spots on rose leaves indicate fungal diseases.

The picture shows a rose leaf affected by black spot. Similar symptoms are noted with purple spotting, septoria, cercosporosis.

Treatment will be the same in all cases. Its main component is the competent preparation of roses for winter, which reduces the infection of plantings, increases the resistance of roses and does not have to be applied too often. chemicals protection.

- In September, be sure to feed the roses with potash-phosphorus fertilizers. Potassium reduces the susceptibility of roses to fungi.

- In mid-autumn, preparing roses for shelter, cut off all non-fallen leaves and severely affected parts of the shoots, carefully collect all debris and burn, dig trunk circle, then sprinkle the roses with a solution of ferrous sulfate (3%).

-In the summer at the first appearance dark spots on rose leaves, spray them with preparations containing mancozeb (Profit, Ridomil Gold) or triazole (Skor, Topaz). For most varieties, if the autumn hygiene measures are well done, such treatments are rarely required.

Rose rust.

The occurrence and spread of rust in roses is facilitated by dry and hot weather. On the underside of the leaves, on the petioles, sepals and fruits of a diseased rose, orange-rusty pads of summer spores of the fungus appear. By the beginning of autumn, the rust fungus develops winter black spores on the underside of the leaves. Rose leaves affected by rust turn yellow, die off and fall off; shoots are stunted.

At the first sign of rust, diseased roses are sprayed with Bordeaux liquid (1%), if necessary, repeating the spraying after 10 days. Also, when rust pads appear on roses, you can periodically spray the plants with copper chloride or copper-soap solution (after 10 days).

Fallen leaves affected by the fungus are collected and burned. In autumn and spring, diseased shoots of roses are cut and destroyed, the soil in the rose garden is dug up. In the spring, the bushes and soil around the roses are sprayed with a solution iron vitriol (3-5%).

Downy mildew (caused by fungi of the genus Peronospora, Plasmoparma), etc.) - easy to confuse with a previous disease. The difference is that with downy mildew, the underside of the leaf is covered with a white fluffy coating of fungal spores. And on the upper side of the leaves you can see light or yellowish spots. Downy mildew spreads primarily on wet leaves.

Control measures. In diseased plants, affected shoots, leaves, buds are removed, the plant is treated with a fungicide, for example, Planriz, Fitosporin, Alirin-B.

Gray rot, or botrytis in roses.

The causative agent of gray mold is the fungus Botrytis cinerea, which infects about 200 various kinds plants. In roses, buds with pedicels, the ends of young stems and leaves mainly suffer from botrytis; in wet weather they are covered with a gray fluffy coating. First of all, this rot attacks weakened roses, and most often - with white and light pink flowers. The buds on roses affected by botrytis do not open, rot and fall off. Small brown spots (sores) appear on the petals, the leaves turn yellow and also fall off. Young roots of cuttings are also affected by gray rot.

Foci of infection persist in plant remains in the form of mycelium (mycelium), which forms spores in spring. The spores are then dispersed by insects and the wind. Therefore, an undesirable "neighbor" for roses is, for example, garden strawberry, often suffering from botrytis.

Control measures. Preventive are the same as for other diseases. As a therapeutic measure, treatment with one of the fungicides will be required. At initial stage diseases will help the biological product Alirin-B.

Black spotted roses. How to identify the disease and cure the plant. How to prevent infection. How to protect yourself from infection (10+)

Black spotted roses

The material is an explanation and addition to the article:
Plant Diseases - Overview
The plant is sick. How to define a disease? Species, types, classification of plant diseases and pests. Treatment Tips

black spot- the same familiar disease of roses, like a cold for a person. It is very common, few varieties of roses are immune to this disease. The disease becomes apparent around July, but some species can get sick even in the spring.

Black spot is caused by spores of a fungus from the genus Septoria, Marssonina rosae, plants can become infected even with an infected pruner. Spores, when they hit the plant, populate the leaf and are visible as dark brown spots, then the fungus multiplies rapidly, the leaf turns yellow and dies.

Leaves and shoots must be destroyed by burning, because the spores can easily overwinter in the soil and re-infect the plant in the spring. Everyone who has planted roses in their area should take care and be kind to them, because this plant is very delicate.

Try to choose the most resistant varieties roses, because some varieties are genetically predisposed to this disease, and it will be difficult for you to fight it. The place where your roses are planted also matters - in dense, shady places where moisture will evaporate longer, you should not plant bushes, where the disease will spread faster.

• An effective method of combating fungal and bacterial diseases, including spotting different nature

pruning

We all know that prevention is better treatment. Let's start with the fact that the first preventive measure is pruning. A properly pruned rose will be stronger and more disease resistant than a rose with emaciated and damaged shoots. Unadapted varieties should also be treated according to the following scheme: for the first time - as soon as the leaves have blossomed and after about a week, before flowering, with a solution of Oxychoma or copper sulphate.

In rainy and cool weather, you should find time to trim the bushes, remove weeds and fill the ground around the rose, as well as treatments with biological products such as Alirin B, Gamair, mancocerb-, penconazole- and triazole-containing preparations to preserve your delicate garden decoration. Leaves are almost completely shed from a black-spotted bush. Most roses cannot survive the attack of this enemy, grow a new "hair", and die.

After the end of winter, with the onset of a warm spring, we often assure ourselves that the rose is just still in “hibernation”, a little more, and it will delight us with its leaves, later with flowers. But, in fact, the bush, most likely, was sick. This fungus kills many more roses in winter than in summer.

Treatment Methods

Treatment for black spot infection - removal of all infected shoots, leaves and other parts of the bush, spraying with copper-containing fungicides, it is advisable to alternate them. There are 3 types of drugs: systemic, contact and contact-systemic. Contact and systemic-contact - copper sulfate, hom, active copper, that is, all copper-containing "drugs", they destroy fungal spores, but these drugs do not always help in the fight against black spot.

Systemic and contact-systemic "drugs" - acrobat, mts, ordan, profit gold, fundazol, fast, tend to treat the plant from the inside, penetrating through the tissues. But you can not use the same fungicide, because. mushrooms tend to get used to it. It is for this reason that drugs should be alternated and not overdone, they should be used no more, no less, but as indicated in the instructions.

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