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When cucumbers bloom but do not bear fruit: what to do? We clarify the causes and give the solutions!

When cucumbers bloom but don’t bear fruit, it can frustrate any gardener. You’re probably wondering why this problem happens and what you can do about it. Failure to produce fruit can be caused by poor pollination. The varieties you grow also matter. Growing conditions (such as temperature, weather and nitrogen levels) also affect pollination and flower formation. Sometimes you just need patience to get fruit from your plants. However, there are also times when you can take steps to encourage fruiting. In this article, we’ll talk about why cucumbers flower but don’t fruit. We will also give you some ideas on how to solve the problem.

How varieties affect production

Cucumbers can be divided into 3 types - monoecious, gynecous and parthenocarpic

Cucumbers can be divided into 3 types: monoecious, gynoecious and parthenocarpic. Depending on the type of cucumber, you may need more than one plant for pollination and fruit production.

  • Monoecious species form both male and female flowers on the plant. Although the plant produces both male and female flowers, they do not necessarily bloom at the same time. In cucumbers, it is common for the male flowers to appear first, sometimes a week or two before the female flowers. This time difference can sometimes result in poorer pollination.

When cucumbers bloom but don't fruit - We explain how to increase fruit production

  • Gynoecious varieties generally have only female flowers on the plant, although in some cases some male flowers may appear. The main advantage of these types of cucumbers is that they produce more female flowers, which can result in a higher yield per plant. For this reason, these varieties are often used in commercial production.
  • The parthenocarpic type is a variety that can bear fruit without pollination, but the fruit does not contain seeds. The main advantage of this variety is that it can bear fruit without pollination, which is an advantage when growing cucumbers in greenhouses. The main disadvantage is that the fruits do not contain seeds, so no seeds can be saved for the next year. Some common parthenocarpic varieties are Sweet Success, Diva, Tasty Jade and Telegraph.

When cucumbers bloom but do not bear fruit: causes.

How do cucumber varieties affect production

The main reason for this problem is that the fruits have not been pollinated, so the plant does not put extra energy into developing the fruits because no seeds develop. There can be several reasons for this:

  • The number of pollinators present is low or they are inactive. (This may be the case in rainy weather).
  • The cucumber variety grown is a hybrid variety that produces only female flowers on the plant.
  • Fruiting is affected by unfavorable climate or soil conditions.

To determine what is causing the problem, look for male flowers on the cucumber (how to tell the difference between male and female flowers is explained later in the article). If no male flowers are present, you will need to plant a second cucumber variety that produces male flowers (monoecious). If male flowers are present, hand pollination is required to ensure fruit production.

How to increase fruit production

The number of pollinators present is low or they are inactive

To improve the fruit production of plants, two basic things must be done. The first is to increase the number of male flowers, and the second is to increase the pollination rate of female flowers. The most effective method is to increase the number of monoecious plants in your garden. Since these varieties produce both male and female flowers, the number of male flowers naturally increases. Since male flowers are capable of pollinating many female flowers, you only need a few plants to make a significant difference. However, it is important to note that, as mentioned above, there is a slight timing difference in the production of male and female plants that can affect pollination.

When cucumbers flower but do not bear fruit: increase pollination rate.

When cucumbers flower but do not bear fruit -Increase pollination rate.

The simplest way to hand pollinate cucumbers is to use a fine brush. The brush is an effective tool for transferring pollen from male to female flowers.

  • To pollinate, look for the male flowers on the cucumber canes. Gently press the brush into the center of the flower and rotate it a few times to collect as many pollen grains as possible.

Growing conditions also affect pollination and flower production

  • Place the brush with the collected pollen on the center part of the female flower and gently move the tip of the brush over the flower. This will ensure that the pollen grains are transferred to the female flower.
  • Dip the brush into another male flower and continue the pollination process.

An alternative to hand pollination is to use a conventional spray for pollination

Alternatives to hand pollination
An alternative to hand pollination is to use a conventional spray to pollinate your cucumbers. The spray contains kinetin, a plant hormone that causes the flowers to bear fruit even without pollination. It’s best to spray it on the flowers and surrounding foliage once a week when the flowers appear.

Difference between male and female flowers

Learn the difference between male and female flowers

The easiest way to identify a female flower is that it bears a small, undeveloped fruit behind the flower. The fruit develops only when it is pollinated. Also, the flower appears alone and not in a bouquet. Male cucumber flowers have shorter and thinner stems that support the flower, and often appear in groups of 3 to 5 flowers. Their only function is to provide pollen for the female flowers; they do not bear fruit. Some examples of monoecious varieties are Marketmore, Itachi Lemon, and Striped Armenian.

Other factors that influence fruit production

The climatic conditions and the nutrients in the soil are other factors

In addition to plant choice, general climatic conditions and soil nutrients are other factors that can affect performance.

  • Temperature can significantly affect flowering in cucumber plants . If you live in regions where unpredictable late frosts are common, your plants are more vulnerable. Low temperatures below 10 degrees Celsius can slow growth and damage plants. A freeze will kill the plants. When it is hot, a plant tends to produce more male flowers. When temperatures are cooler, a cucumber plant produces more female flowers. To reduce the likelihood of cold weather problems, it is advisable to use a row cover as it protects the plants from frost and cold weather.

When cucumbers flower but don't bear fruit, it can frustrate any gardener

  • Nutrients in the soil also affect the formation of flowers. Cucumber plants are known to be relatively heavy growers and have high nutrient requirements. However, if too much fertilizer is added to the soil, the roots can be burned. In addition, excess nitrogen can cause the plant to produce more leaves, which can delay the onset of flower formation. To avoid this problem, it is best to feed the soil with compost instead of fertilizer , as this generally provides the plant with a wide range of nutrients, but not excessive amounts of nitrogen.