Foliar feeding of cucumbers: timing of application, types of fertilizers

For high-quality growth, cucumbers require a full range of vitamins and minerals, as well as protection from pests and viruses. Foliar feeding can boost immunity. For this you can use chemicals or folk remedies.

Why is fertilizing necessary?

Foliar feeding of cucumbers can serve several functions: strengthening, stimulating growth, protecting, and replenishing micronutrient deficiencies. This method typically involves a simple spray. It differs from root feeding only in that it doesn't disturb the soil and is applied directly to the leaves or fruits. Its advantage is that it reaches the affected areas directly, making it more effective in cases of disease or localized damage.

Furthermore, foliar feeding of cucumbers in a greenhouse or open ground has no effect on the soil: it neither increases nor decreases its acidity, making it suitable for use in virtually any conditions. Its targeted and localized application isolates the active ingredients and avoids affecting other plants, which is important if you're growing several crops in the same bed. Foliar feeding is necessary:

• in pest control;
• to replenish mineral deficiencies;
• as a means of combating diseases;
• to strengthen the immune system;
• eliminating problems not related to the root system of cucumbers;
• with local impact on a specific plant or area.

The effectiveness of foliar feeding depends on the problem and the product you're applying. If you need to target the leaves—for example, to control spider mites or aphids—then apply the product to the leaves and stems. Root rot, however, is treated by directly applying the active ingredient to the soil or roots. Spraying can be used not only when the problem has become apparent but also for disease prevention or insect repellent.

Basic rules

Spraying is localized and effective, with the first improvements noticeable within a few hours. However, to ensure the product works properly and achieves the desired effect, a few simple rules should be followed.

1. Adjust your fertilizer dosage. Too high a concentration of nutrients can harm crops rather than improve their growth and resilience.
2. Start feeding with small amounts, then increase if the plant still needs more. Cucumbers need time to adjust, and you need time to assess their response.
3. Spray only in calm, dry weather. Morning or evening, when the sun is not too bright, are best. Direct sunlight will burn and damage the leaves. Wind will simply prevent the product from sticking to the bushes.
4. Use spraying as a preventative measure. The pungent smell of ammonia or pepper solution can repel unwanted insects from cucumber plants.
5. When fighting pests, use soap: it will help the solution adhere to the green parts of the plant.
6. If you grow cucumbers in the same bed with other plants, try to ensure that the substances do not come into contact with them during spraying.
7. Clean spray containers to prevent residue from previous solutions from accumulating in them.
8. Use protective equipment to prevent the product from coming into contact with your skin or inhaling it. Wear a respirator, thick rubber gloves, and eye protection with goggles.

In addition to prevention and nutrition, spraying helps maintain optimal humidity levels. For cucumbers, this is 70-80%. Spraying water can save crops during particularly hot, dry periods and normalize the microclimate in the greenhouse.

Terms and methods of contribution

Feeding cucumbers It's necessary throughout the entire growing season, right up until harvest. Unlike root watering, misting allows for even distribution across the entire plant, targeting the problem locally without affecting healthy areas. Mineral support is important at every stage:

• when transplanting seedlings into the ground;
• during active leaf formation;
• during the flowering period;
• during the formation of ovaries;
• during the period of active fruiting.

It's especially important to replenish micronutrient deficiencies to prevent plants from starving. The problem can be noticed by leaves curling, losing their color, and gradually falling off. These signs may indicate not only a mineral deficiency but also a disease: it's important to recognize the symptoms promptly and treat the plant with the appropriate treatment. Typically, fertilize every 1.5 weeks, or 4 to 6 times per season.

Fertilizers, insecticides, and fungicides are applied using a watering can or sprayer. The nozzle should be fine enough to atomize the substance effectively. It's best to use separate containers for fertilizers and insecticides, or disinfect them before each use to prevent the substances from mixing and causing a chemical reaction. Treat containers with detergents, iodine or chlorine solutions, or boiling water. After washing, rinse with water and dry thoroughly before adding new solutions.

What to feed

Cucumbers require different minerals at different stages. During the early stages of growth, nitrogen is crucial: it accelerates the development of foliage and promotes stem and shoot growth. During flowering, potassium is essential; it helps ovary formation and improves metabolism. Phosphorus is most important during the final stages, when fruit is forming. Fertilization helps fruits become juicier and tastier.

Fertilizing is necessary not only as a preventative measure but also during periods of deficiency. Sometimes it's difficult to determine which mineral fertilizers a plant currently lacks. In this case, you can apply supplemental fertilizers one after another, monitoring the plant's response, or purchase a combination fertilizer that addresses most common problems.

Urea

This fertilizer is sold in granules and is used to accelerate the growing season. Indications for use: nitrogen deficiency, aphid and weevil control. A nitrogen deficiency leads to weakened bushes, yellowing and leaf drop, and reduced yields. Urea It does not affect the soil, so it can be applied in any way, but spraying is a more effective and faster method.

The first application of fertilizer is immediately after transplanting the seedlings into the soil, or after a few leaves appear if you planted the seeds directly into the soil. A second application of nitrogen fertilizer is made 10-14 days later, unless urgently needed. Once fruit begins to set, supplemental feeding can be stopped.

Urea dissolves well in water. You need about 15 grams of the solution per bucket. Spray the resulting solution evenly onto the leaves and stems. Use the solution immediately, so avoid preparing too much. Store the dry urea in a cool, dry place.

Boric acid

A good fertilizer that helps increase yields. The plant receives oxygen, metabolism improves, and the fruits are enriched with calcium, enhancing their flavor. This can be applied to both mature plants and seedlings: this will strengthen the cucumbers' resistance to disease and improve their tolerance to temperature fluctuations.

Boric acid It's best applied in the early stages, before fruit appears. It helps eliminate yellow spots on leaves, increases ovary production, and prevents fruit and stem drop. Add 10 grams of the active ingredient to a bucket of water. The water should be warm to allow the ingredients to mix. Cool the solution to room temperature before watering.

Calcium nitrate

Fertilizing cucumbers with calcium nitrate improves cell health, boosts immunity, and has a positive effect on the quality and quantity of the harvest. It also protects crops from slugs and spider mites. This fertilizer is effective in even the most challenging conditions: cold, temperature fluctuations, excessive moisture, or dryness. It positively affects the formation of cell membranes, reduces the plant's sensitivity to climate change, and protects against diseases. Fruit from cucumbers fertilized with nitrate lasts longer, and the cucumbers themselves taste better.

Add 20 grams of the substance per 10 liters of water. Spray during the growing season at intervals of 8-10 days. Fertilizing cucumbers ceases during fruiting.

Iodine

Crops are most fragile when the first flowers appear. To protect cucumbers from diseases and pests, they are sprayed with a solution of iodine and milk, which improves the plant's resilience and allows it to better withstand threats. To prepare it, use:

• 15 drops of iodine;
• 500 ml low-fat milk;
• 5 liters of water;
• 40 grams of grated laundry soap.

Soap is needed to fix the mixture onto the leaf blade. The resulting solution is used every 1.5 weeks from the moment the first leaves appear. Iodine acts as a disinfectant, preventing fungal diseases and root rot. Milk forms a film that covers the leaf, protecting it.

A more concentrated solution helps eliminate existing signs of infestation. To do this, dilute the iodine with water at a 1:2 ratio and then apply it to healthy areas using a spray bottle. Remove affected leaves and stems to prevent the infection from spreading.

Traditional methods

Chemicals and complex fertilizers should only be used during the early stages of vegetation, when they are safe. Once fruit appears, it's better to switch to safer methods: biological preparations or folk remedies. The latter option is cheaper, and you can make your own fertilizer from ingredients you have at home.

Yeast

Yeast feeding Provides plants with vitamins and minerals. Yeast contains carbohydrates, proteins, vitamins, and minerals. When dissolved in water, it forms compounds that positively influence cucumber growth. This fertilizer should not be combined with substances containing other beneficial bacteria, as well as with grass and manure, but the yeast solution is resistant to temperature fluctuations and works in virtually any conditions.

Fresh yeast is diluted with warm water at a ratio of 2:10 and left to steep. Afterward, dilute with the same amount of water and water the plants. If using dry yeast, prepare it a little differently:

1. Bring 1.5 liters of water to 40 degrees.
2. Add 5 tablespoons of sugar and 5 grams of yeast.
3. Leave the solution to infuse for half a day, stirring occasionally.
4. Dilute the concentrate with water in a ratio of 1:3.5.

Onion peel

This folk remedy effectively protects against pests and helps strengthen the immune system. It contains beneficial microelements, including phosphorus and potassium, which are essential for plant development. The solution is prepared from 40 grams of onion peels and a bucket of water. Infuse in a warm place for 96 hours, filter, and then use for spraying. The remaining peels can be used as mulch.

As a preventative measure, the solution is used once every 1.5-2 weeks, and if pests have already appeared in the garden, the frequency of spraying is increased to once every 5 days.

Herbal tea

This herbal supplement strengthens plants and enriches crops with nitrogen. It's prepared using green parts of plants and weeds. They are finely chopped, soaked in 10 liters of water, and left for 48 hours. The resulting infusion is strained and then sprayed on cucumbers to protect against powdery mildew and fungi.

The nuances of foliar feeding

Fertilizing by spraying is done in a similar manner in open ground and greenhouses. Greenhouses have their own microclimate, with limited air circulation and controlled temperature and humidity. Spraying can be done safely, as long as the air humidity remains within the recommended limits.

In open ground, spray the substance carefully and only in windless weather, otherwise it will miss the target. Outdoor plants should not be fertilized during the middle of the day, especially in hot weather, as direct sunlight can burn the leaves.

If you overdo it with fertilizer, the plant may get burned, begin to wilt quickly, or lose some of its yield. If you overdo it, reduce the amount of fertilizer, limiting the application to just clean, room-temperature water. Spray the leaves to remove any residual fertilizer. Return to foliar feeding only once the plant returns to normal.

During fruiting, avoid using harsh chemicals, as they can damage the fruit by accumulating toxic substances. To ensure a safe harvest, use only natural remedies after flowering; they won't harm the crop or impair the taste of the cucumbers.

Foliar feeding is a good way to address the problem locally. It helps protect against insect pests, mineral deficiencies, and common diseases. Spraying is done from a spray bottle, and the solution can be anything from chemicals to folk remedies. It can be used for treatment or prevention. Foliar feeding does not disturb the soil, so any product can be used without concern for interaction with the soil.