Why are there so many barren flowers on cucumbers and what can I do about it?

Gardeners, especially beginners, often face a difficult situation. Cucumbers appear to be blooming, promising a good harvest, but instead of the expected fruit, there aren't even any ovaries. Experienced gardeners know what to do with barren flowers on cucumbers, how to regulate the development of female and male flowers, and how to prevent cucumbers from blooming entirely with barren flowers.

What is a barren flower?

To understand why cucumbers develop barren flowers, we need to understand why some flowers produce fruit while others don't. Cucumbers are bisexual plants.

1. The fruits grow from female inflorescences – pistils.
2. Stamens—male flowers—are needed to pollinate the female flowers. They are called sterile flowers because they do not bear fruit.
3. They usually develop at the beginning of the stem, followed by pistils (female flowers), which alternate. Their number increases on the lateral branches and at the crown of the stem.

More female flowers means a higher yield. Some gardeners try to quickly remove empty flowers, believing that their blooming drains the plant's energy.

However, experienced vegetable growers believe that there is no need to get rid of barren flowers, since without them, the female flowers will wither, fall off, and even rot.

Removing barren flowers will weaken the plant's immune system, hinder its development, and prevent pollination of female flowers. Gardeners recommend removing (pinching) the top of the main stem with scissors.

Causes of barren flowers on cucumbers

There are many factors that cause cucumbers to bloom with empty flowers:

• poor quality seeds;
• watering errors;
• too hot or cold weather;
• lack of light;
• very frequent landing.

A detailed examination of the reasons for empty flowering is below.

Poor quality seeds

When choosing seeds from a reputable manufacturer, you can be sure that the seeds are high-quality, viable, and ready to plant. It's advisable to purchase seeds from reputable producers. When harvesting seeds on your own, gardeners, especially novices, can make mistakes, and the resulting harvest will be disappointing.

Important: When harvesting seeds, you should use female cucumbers, not male ones.

They differ in the number of seed chambers (males have 3; females have 4) and in their edges. Male cucumbers are triangular, while female cucumbers are tetrahedral.

Sowing seeds that are too young

One of the factors in the development of barren flowers on cucumbers is the age of the seeds, so it is necessary to sow the “right” seeds.

1. Seed material that has been stored for two to four years.
2. If you don't have time to wait, you can "age" them. To do this, treat the seeds with heat. For example, warm them up before sowing by placing them on a radiator.
3. You can soak the seeds in a special growth accelerator solution (Epin, Novosil, Zircon, and others). The soaking time is indicated on the packaging.

This method is suitable for most varieties of cucumbers.

Incorrect watering

It turns out that watering cucumbers also requires careful consideration. Avoid using water colder than 20°C for seedlings. This leads to fruitless blooms. Water thoroughly every day while the stems and fruit are growing.

Experienced gardeners recommend so-called “shock therapy.”

When flowering begins, do not water the plants until the ovaries have formed. This shock promotes the development of female flowers. Once the ovaries have formed, return to normal watering.

Heat

Cucumbers are a heat-loving crop. However, summer heat hinders plant growth and fruit set. Sweltering heat kills the pollen in male flowers, rendering it inviable.

Increased watering (early morning and late evening) when the sun is setting will help save the harvest. Mulch is also helpful. It retains moisture and inhibits weed growth.

Cold weather

Rainy, insufficiently warm weather (below 15°C) inhibits plant growth and the development of female flowers. A high yield cannot be expected during prolonged cold spells. It is advisable to stop watering the plants for a while, at least until warmer weather returns.

Insufficient lighting

A common cause of barren flowers on cucumbers is insufficient sunlight.

1. Once a shaded area has been chosen for planting cucumbers, watering the plants should be reduced.
2. This problem also often occurs in greenhouses. It's necessary to cut off the top of the main stem, which will accelerate the growth of the side branches. Only on these branches do female inflorescences form.

Incorrect feeding

It's not advisable to fertilize cucumbers too frequently. Don't overdo it with nitrogen. The plant will begin to "grow fat," putting on a lot of foliage and even bloom, promising a decent harvest. But all that will happen is a barren crop of flowers.

1. Nitrogen fertilizers are applied 10-15 days after planting.
2. Then the cucumbers are fed with a mineral complex (potassium, phosphorus).
3. Water once a week with organic fertilizer, such as mullein or herbal infusion. Dilute 1 liter of the working solution in 10 liters of water.

Crop density

One of the reasons cucumbers fail to bloom is the frequency of planting. The problem arises when the cucumber planting pattern is not followed.

Plants are experiencing a lack of air and light, and their growth and development are poor. Pollination is also difficult. It's not surprising if the flowers are completely barren. Once the cause of the barren flowers is identified, it must be addressed to avoid disappointing harvests.

Barren flower in a greenhouse

Barren flowers on cucumbers often appear not only in unprotected soil but also in greenhouses. Pollinating insects have difficulty accessing the greenhouse. There are several simple solutions:

1. You need to open the greenhouse door more often and keep it open longer.
2. You can artificially attract bees. For example, by spraying plant leaves with a honey solution (2 teaspoons per 1 liter of water). Inexperienced gardeners, hoping to attract bees, often place a jar of honey in the greenhouse. This is a mistake. Spraying the plants is sufficient.
3. Hand pollination is used (a traditional method). Early in the morning, a male flower is picked and the stamen is applied to the stigma of a female flower. It is advisable to fertilize the female flower with not just one, but several (2-3) male flowers.

Methods of dealing with the problem

If cucumbers have barren flowers: what to do to regulate the growth of female flowers:

1. Follow watering guidelines and water temperature. Stop or reduce watering based on weather conditions.
2. Pinch the main stem of plants if they are planted close together and lack light. For early-ripening varieties, the top is cut off above the 10th leaf; for late-ripening varieties, earlier (above the 8th leaf).
3. For better ventilation and air access, proper garter is necessary.
4. In order to form ovaries, it is necessary to feed the plants correctly.
5. If pollination is insufficient, manual pollination or spraying the plants with a honey solution will help.

To combat barren flowers, products that regulate the development of male and female flowers, such as Borogum, Bud, and Ovary, can help. Instructions for use are provided by the manufacturer on the packaging. These products stimulate plant growth, accelerate the formation of ovaries and fruits, without adversely affecting the nutritional value of cucumbers.

Preventive measures

By using certain techniques, you can avoid the appearance of barren flowers.

1. Planting self-pollinating cucumbers. They are called parthenocarpic. They produce few barren flowers. All hybrids are self-pollinating.
2. If you decide to plant varietal cucumbers, take a responsible approach to choosing planting material.
3. The fruits need to be picked more frequently. This ensures the formation of new ovaries and accelerates the growth of other cucumbers.
4. To achieve consistent yields, it's essential to care for the plant at every stage of its growth—from sowing the seeds and growing the seedlings on the windowsill to planting the seedlings in the ground and harvesting.

Barren flowers on cucumbers: what to do? This problem can be eliminated by following simple recommendations from experienced gardeners. And if barren flowers do appear, how to deal with them is now clear. With careful and skillful care, the cucumber harvest will be a delight.