Tips

Diseases of roses and methods for their treatment


A variety of diseases and plant parasites can cause quite serious damage to the garden rose, sometimes leading to the death of a flower crop. Before starting the treatment of roses, one should not only clarify the damaging factors, but also find out how the most effective fight against them is carried out. It should be noted that roses are sick not only with non-infectious, but also with many infectious diseases, so you should start fighting the lesion as soon as possible.

Infectious diseases of roses

The optimal arrangement of flower culture in the infield and adherence to growing technology significantly reduces the risk of rose infectious diseases.

However, even the most resistant varieties are not immune to disease damage in adverse weather conditions, as well as low light, thick plantings and poor ventilation. Also, this popular decorative culture often suffers from mechanical damage., which may be the "gateway" for the penetration of fungal, viral or bacterial infections.

Type of lesionDisease nameSigns of defeat
Fungal infectionsPowdery mildewA very characteristic white, powdery coating appears on the foliage and stems.
RustThe appearance of very typical, orange-yellow staining of spores on the shoots and lower leaves
Black spottingThe formation on the foliage of purple-brown, blackening over time, rounded spots, falling leaves, slowing down the development of shoots and loss of frost resistance
Infectious burnThe formation of brown spots in the early spring with reddish-brown fringing on the shoots of roses
Gray rot or botritisIn wet weather, the buds and pedicels are covered with a clearly visible gray coating
Bacterial infectionBacterial burn or stem cancerThe leaves curl, dry out, and the bark acquires a pronounced brown color and dies.
Viral infectionBand virusThe formation of dark coloring of the edging along the contours and veins of sheet plates
BronzeThe appearance of whitish spots on the foliage and brightened leaf veins
Viral wiltDeformation of leaves on the bush, sprouting shoots and the complete absence of buds
Viral necrosisThe appearance of spots of necrosis on leaves that darken and then massively fall
Mosaic of crescentAppearance of round necrotic spots and chlorosis on foliage

Noncommunicable Rose Diseases

As a rule, non-infectious rose diseases are the result of gross violations of growing technology. Improper agricultural practices, including non-compliance with irrigation and top dressing, often cause non-infectious lesions of rose bushes. Most often, problems are associated with a violation of the diet of decorative culture.

Rose Disease: Treatment

MalnutritionSigns of illnessPreventive and therapeutic measures
Nitrogen deficiencyFoliage loses its green color, red dots appear, and leaf blades become very narrowDressing a decorative plant with a solution of urea or ammonium nitrate at the rate of a tablespoon per bucket of water
Excess nitrogenThe foliage acquires a dark green color, the growth of the aerial part to the detriment of flowering is enhanced, the resistance to damage by fungal infections decreasesReduce the use of nitrogen-containing fertilizers
Phosphorus deficiencyViolet-brown staining of the strip and spots is formed at the edges of the foliage, shredding of the foliage and stunting growth are observedFeeding roses with a solution of superphosphate at the rate of a tablespoon per bucket of water
Potassium deficiencyYellowing of the foliage, and further wrinkling and the appearance of reddish-purple staining of the leavesPlant nutrition with a complete complex fertilizer with a high potassium content, diluted at the rate of a tablespoon per 10 liters of water
Excess potassiumWeakening of the aerial part of the plant, the death of peduncles, stopping the development of the root system of the plantFeeding rose bushes with calcium nitrate
Magnesium deficiencyThe formation of discolored spots on the leavesTop dressing of ornamental culture with a complete complex fertilizer with a high magnesium content, diluted at the rate of a tablespoon per 10 liters of water
Lack of iron and manganeseDamage to bushes with chlorosis, resulting in yellowing and discoloration of the leavesSpend a couple of foliar dressings. Spray the aerial part with iron-containing preparations. You can treat the plant with 0.5% manganese sulfate
Boron deficiencyThe shoot growth point dies, the foliage is deformed, the edges of the leaves are bentClose up wood ash in the soil around rose bushes

When choosing the method of fertilizing and the composition of top dressing, it is important to remember that an excess of nutrients can inhibit the growth and development of roses, so the main dressings are carried out no more than twice a year. Experienced agronomists recommend the first treatment and top dressing of rose bushes after winter, in the initial phase of the growing season. The second top dressing is preferably performed at the end of summer using full mineral fertilizers. Weakened by improper care and depleted by pathogenic microflora, roses often die during the wintering process.

Treatment methods

As a rule, the main treatment consists in the correct and timely use of modern, most effective drugs. Plants should be sprayed in dry, preferably slightly sunny weather, which will allow the active substance to effectively combat the damaging factor. Important to remember, that some ailments, including streak virus, rhesus mosaic virus, viral wilting, and bacterial cancer, cannot be treated, therefore it is recommended to scoop up and destroy bushes affected by these diseases.

Type of lesionUsed drug or remedyTreatment regimen
Fungal infections, including powdery mildew and rustIron sulfate, potassium sulfate, colloidal sulfur, Benomil, Tsineb and FundazolSpraying in autumn or early spring with a 3% solution of iron sulfate with the addition of a 0.3% solution of potassium sulfate or Bordeaux mixture. Twice a month, treat the aerial part with a copper-soap solution or 1% suspension of colloidal sulfur or replace them with 0.25% Benomil, 0.4% Tsineb or 0.1% Fundazole "
Black spottingModern drugs "Profit", "Ridamil-gold", "Topaz" and "Skor"Processing the aerial parts of the plant with solutions, alternating the preparations: Profit, Ridamil-Gold, Topaz and Skor
BotritisAny antifungal insectofungicidal agentsProcessing the aerial parts of the plant with Fundazole, Benlat and Teldor, as well as spilling the soil around the bushes with a solution based on the Maxim preparation
Necrosis of the cortexBordeaux mixture, the drug "Abiga peak"Spraying the aerial parts before foliage blooms with Bordeaux liquid, a solution based on the Abiga Peak preparation or its substitute
Ramulariosis, cercosporosis and phylostictosisPreparations based on the active substance mancozeb or triazoleAlternating treatment of the aerial parts of the plant with Profit, Ridomil Gold, Topaz and Skor preparations at the dosage recommended by the manufacturer

Prevention Tips

Despite the fact that the work of domestic and foreign breeders in recent years is aimed at breeding not only highly decorative, but also disease-resistant varieties, only the correct prevention of rose diseases allows you to get the most decorative, abundantly flowering and long-lasting plant. Preventive measures are as follows:

  • splashing water during irrigation measures on foliage is one of the main reasons for the development of fungal diseases, therefore it is necessary to water rose bushes exclusively under the root;

  • the plants do not need a significant amount of nitrogen-containing complexes, and the excessive introduction of nitrogen often causes an increase in the susceptibility of the ornamental culture to disease damage;
  • good prophylaxis of powdery mildew lesions is soda treatment, which should be carried out twice a week with a solution based on a teaspoon of soda, diluted in a bucket of water;
  • as prevention of damage by gray rot, manganese top dressings are used, which increase the plant's resistance to this fungal infection;

  • in order to prevent damage to the most common fungal diseases, it is necessary to remove fallen leaves in a timely manner and conduct relatively deep soil treatment around the bushes, followed by spilling with a solution based on the Maxim preparation;
  • it is necessary to regularly remove and destroy all parts of rose bushes affected by diseases.

Rose Pests: Fight

For flower growers, especially beginners, it is very important to remember that in order to reduce the risk of hurt roses and pests, it is necessary to use an exceptionally clean garden tool, as well as conduct regular visual inspections of the bushes to quickly detect the first signs of infection.