How to get rid of powdery mildew on cucumbers: control measures

Powdery mildew is a fungal disease that affects the leaves and stems of any vegetable. The fungi colonize the epithelial cells of green plants, causing a whitish coating—mycelium—to form. Incubation of the fungal disease takes approximately 3-5 days. It can occur if the soil is overdried or overwatered, or if the topsoil is wet and the soil is overwatered.

Causes and signs

After infection, the following symptoms appear on cucumbers: a fluffy white coating appears in spots on the surface of the leaves and stems of the vegetable, and the leaves begin to wither.

You can get rid of powdery mildew on cucumbers using folk remedies and chemical preparations.

The fungus thrives on cucumbers in warm, humid climates. Summer rains in warm weather, lasting several days, cause a white coating to appear, followed by yellowing of the leaves. Causes of the disease:

1. Warm weather with air temperatures of 16-22 degrees Celsius. Sunlight also promotes infection.
2. They are easily affected by powdery mildew during rapid changes in nighttime temperatures. The plant's immunity is sharply reduced during this period.
3. The cucumbers are planted too close to each other.
4. The soil is oversaturated with nitrogen.

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Chemicals for cucumbers

Chemicals for combating powdery mildew on cucumbers are available at any gardening or hardware store. They are recommended when the fungus has damaged more than half of the crop. The following chemicals are available:

1. Topaz can be applied immediately after signs of yellowing foliage appear. This product is toxic to humans. While treating powdery mildew on cucumbers, do not touch the treated plants. This product is based on penconazole. Dilute one ampoule of the product in 10 liters of liquid. Spray with a freshly prepared solution, and dispose of any leftovers. Repeat treatment every two weeks.
2. Tilt KE, whose active ingredient is propiconazole, prevents further growth of fungal mycelium. It is produced as an emulsion. When the ambient temperature rises, the product is activated and penetrates plant tissue. Prepare a solution: 40 g of emulsion and 10 liters of liquid, mix and stir. Spray the affected cucumbers. After a while, a protective film will appear that will protect for over 14 days.
3. You can treat cucumbers with Thiovit Jet, Rayok, Skor.
4. Colloidal sulfur solution. Use a 20% solution for treatment. Use only in open ground in cloudy weather at temperatures of 20-30°C. Prepare the solution according to the instructions in a non-food container. Apply no more than 3 times per week, no more than 2 times during the entire growing season.

Biofungicides

Biofungicides—bactericidal substances—are becoming increasingly popular. Their advantage is their safety and non-toxicity.

Biofungicides include:

1. Fitosporin, which is made from a bacterial base, slows down the growth and development of fungi, protecting them.
2. Albite, which boosts plant immunity, also helps stimulate shoot development.
3. Gamair is a therapeutic and prophylactic medicine. It boosts the immune system of cucumbers and stimulates soil fertility.
4. Alirin-B has therapeutic and preventative properties. It helps restore the microbiological structure of the soil.
5. Baktofit. It is considered the most effective remedy against fungal diseases. However, after treatment, the fruit should be thoroughly washed with clean running water before consumption.

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Traditional methods

Powdery mildew, a fungal disease, can appear on cucumbers and other crops. At the first sign of infection, prompt treatment is necessary to prevent further spread. Folk remedies include:

1. Soap and wood ash. Prepare the solution as follows: grate the soap and mix it with 200 g of ash. Pour warm water over the mixture and stir until the soap dissolves. Apply to the cucumbers three times a week.
2. Baking soda. Prepare a solution based on the following: 100 g of baking soda and 75 g of copper sulfate per 10 liters of liquid. Mix thoroughly. It is advisable to apply the solution only to the foliage.
3. Garlic. Crush the garlic cloves with their greens and pour the solution over them. Let the solution steep for half a day. Water the cucumber growing areas with the solution. Spray the cucumbers for 14 days.
4. Mullein. Dissolve in water at a ratio of 1:3. Let the solution sit for 3 days. Apply to cucumbers in both regular garden beds and greenhouses.
5. Kefir. Even expired kefir will do. Water the leaves every three days.
6. Potassium permanganate. Prepare a solution: 2 g of potassium permanganate per 10 liters of warm water. Spray all cucumber plants with the solution for 2 weeks or more (depending on the disappearance of disease symptoms).

It is recommended to purchase cucumber hybrids labeled F1. Disease-resistant varieties:

1. Hybrid Princess with improved taste qualities.
2. Early ripening variety Arctic, fruiting begins a month after planting.
3. The hybrid Amurchonok was bred from Avangrad.
4. The climbing indeterminate variety Thumbelina does not require pollination.
5. Grandfather's granddaughter, the fruits of which are covered with white fluff.
6. Chinese disease-resistant - has long fruits.
7. Tiny, ripens quickly, has large fruits.
8. Lenara, resistant to various weather conditions.
9. Pasadena, crops appear 1.5 months after planting seeds.

How to deal with downy mildew

There's a condition called downy mildew on cucumbers. Like regular mildew, it typically damages the foliage. However, this disease doesn't produce a white coating. The leaves appear yellow. Downy mildew is more difficult to control. When the first yellowing appears, begin treatment immediately.

You can prevent the disease by:

1. Ventilate the greenhouse only in the part where the cucumbers are located.
2. Never use ice water for irrigation.
3. Harvest crops on time.

When treating downy mildew, use the same medications and folk remedies as for regular mildew. You can spray the affected areas with Ridomil, Kuproskat, or Oxyhom.

Prevention

Preventing powdery mildew on cucumbers will help you quickly manage the disease and prevent it from spreading. Follow these guidelines for growing and caring for cucumbers:

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1. Purchase only tested, high-quality seeds for planting. Disinfect the seeds before planting.
2. It is better to choose seeds that indicate disease resistance.
3. Before planting seeds or seedlings in a bed, make sure the soil is sufficiently warm. It should be at least 12-16 degrees Celsius.
4. Before planting, the soil should be dug over, weeded, and watered with a potassium permanganate solution. Afterwards, manure can be added.
5. Feed cucumbers several times per season.
6. Weed the beds periodically. Weeds interfere with growth and carry diseases.
7. If you notice several diseased leaves, remove them immediately. This will prevent the fungus from developing further.
8. The remains of vines and foliage after the final harvest should be burned away from the site.

If you properly care for your garden, you won't have to struggle with powdery mildew on your cucumbers. When trouble does strike, immediately begin using folk remedies, biofungicides, or chemicals. Closely monitor the progression of the disease, as chemicals should not be used in the early stages. It's recommended to follow control and preventative measures to keep your harvest unharmed and to cure, protect, or save your cucumbers from powdery mildew. Simple care rules will ensure the health and fertility of any garden.