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Effective methods of controlling diseases and pests of cucumbers

For agronomists

5 min read

GREENHOUSES AND COVERS G

Pest and disease control in greenhouses and open fields

Timely plant protection of cucumbers against pathogens directly affects yield and the commercial quality of the fruit. At the first signs of a mass outbreak of downy mildew (peronosporosis ), it is necessary to immediately change the maintenance regime. Stop irrigation and top dressing of plants completely for one week to reduce humidity in the root zone. To combat the fungus, perform an immediate spraying with a warm solution of Bordeaux mixture.

Applying an ash infusion helps combat powdery mildew (white coating), but this method is ineffective against downy mildew (peronosporosis).

To restore vegetative mass and stimulate the growth of side shoots after a disease, treat the plantings with a weak nitrogen solution. Urea is optimal for this purpose. Additionally, treating plants with metronidazole tablets helps increase their resistance to downy mildew. For better adhesion of the products to the leaves during any spraying, add soap to the working solution.

Disease or pest Composition and preparation of the working solution Treatment regime and conditions
Downy mildew Bordeaux mixture Spraying with a warm (25 °C) solution at the first signs of the disease
Downy mildew (shoot growth stimulation) Urea: 1–1.5 g per 1 l of water 2–3 sprayings at 5-day intervals
Downy mildew (resistance enhancement) Metronidazole: 2 tablets per 10 l of water Foliar spraying
Powdery mildew Mullein infusion: 1 kg of mullein per 3 l of water Strain after 3–4 hours and spray. If left to infuse for 3 days, dilute with water 3 times before application
Powdery mildew (alternative) Potassium permanganate: 5 g per 10 l of water OR soda ash: 30–40 g per 10 l of water Spraying with the addition of 50 g of soap per 10 l of solution
Fungal diseases (comprehensive prevention) 10 l of water, 1 cup of milk, 10 drops of iodine, 1 tbsp of baking soda, 50 g of laundry soap Preventive spraying of plantings
Ascochyta blight, olive spot Potassium sulfate: 0.5% solution Foliar top dressing against the background of reduced air humidity
White and gray rot Mixture: 1 g of zinc sulfate, 2 g of copper sulfate, 10 g of urea per 10 l of water Sprinkle affected stems with crushed coal or chalk, remove diseased fruits, and perform spraying with the solution
Aphids and thrips Wood ash infusion: 3 kg per 10 l of water (infuse for two days) OR garlic infusion: 150 g of crushed cloves per 3 l of water with the addition of 10 drops of ammonia, 1 tbsp of soda, and 40 g of laundry soap Spraying upon pest detection

To increase the effectiveness of liquid treatments, you can use fermented healthy weeds instead of clean water. Chopped weeds are covered with water in a 1:2 ratio, kept for 5–7 days, strained, and diluted with clean water in a proportion ranging from 1:8 to 1:10 immediately before spraying. Against aphids in greenhouses, the method of fumigating plants with tobacco smoke is also highly suitable — it is an effective and safe way to sanitize the greenhouse.

After the growing season and harvesting are complete, be sure to perform a full disinfection of the greenhouse or garden bed. Thoroughly clear the area of plant debris and burn them. Treat the soil with a solution of copper sulfate at a rate of 3 tbsp of the product per 10 l of water. For guaranteed destruction of fungal spores, it is recommended to heat the soil surface with a blowtorch or completely remove the top 5 cm of soil from the plot.

Raw material selection and pickling technology for cucumbers

To obtain firm, crispy pickled cucumbers, it is necessary to strictly control plant nutrition in the garden bed. Excessive application of manure to the crop leads to the fruit becoming soft in jars after canning. The formerly popular pickling cultivar Nezhinsky is now practically not grown due to its low yield and high susceptibility to downy mildew. Modern greenhouse cultivars and hybrids possess excellent pickling qualities if the rules for preparing raw materials are followed.

  • Temperature of the Bordeaux mixture solution — 25 °C
  • Depth of the contaminated soil layer to be removed — 5 cm
  • Salt concentration in the brine — 6%
  • Preliminary soaking time for cucumbers — 7–8 hours

The pickling process is based on preservation using lactic acid, which is formed during the fermentation of sugars. For pickling, choose small, uniform-sized cucumbers of the same cultivar or hybrid, and place them in a common container. The highest amount of sugars accumulates in the second half of the cucumber's growing season. At the same time, young cucumbers contain 1.5 times less sugar than overripe fruits, which is why underdeveloped fruit sets are used for high-quality pickling. The mass of spices should constitute 5–6% of the total weight of the cucumbers.

  1. Soak freshly harvested fruits in cold water for 7–8 hours to restore turgor.
  2. Pack the cucumbers tightly into jars with spices: be sure to use dill and hot pepper; optionally, add garlic, tarragon, and currant, cherry, and horseradish leaves.
  3. Prepare a 6% brine (or dissolve exactly 660 g of salt in 10 l of water), bring to a boil, pour over the pickling cucumbers, and leave the jars open for several days until foam appears.
  4. Drain the brine, bring it to a boil again, pour the hot liquid over the cucumbers, and seal the jars.

To give pickled cucumbers extra firmness, add seeds or inflorescences of amaranth or a few pieces of pharmacy oak bark when packing. To improve the crunch and flavor, add a tablespoon of mustard, a little grated carrot, and horseradish roots to the boiling brine before sealing.

Many people enjoy marinated cucumbers. For this, the pickling cucumbers with spices are first poured over with boiling water for 20—30 minutes. Then it is drained, boiled once more, and before the second pouring, salt, sugar, and apple cider vinegar are added to a three-liter jar in equal quantities (a 100-gram glass filled to 4/5). After this, the jars are sealed.

Cucumbers preserved using the methods listed above cucumbers can be kept in an apartment.

If there is a cellar, the pickling cucumbers do not need to be sealed. The cucumber fruits packed in jars with the addition of spices and 2 tbsp. of salt are covered with cold spring water and placed in a cellar, covered with new polyethylene lids. After 2 weeks, add 1 tbsp. of mustard to each to prevent the development of mold and seal again with polyethylene lids.

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