Why does cucumber only bloom but not bear fruit?

Cucumber is an annual herbaceous plant belonging to the genus Muskmelon of the Cucurbitaceae family. It is grown in most provinces of China. Due to the large market demand, the area of ​​cucumber cultivation has increased year by year. However, some farmers will encounter some problems in the process of cucumber cultivation. So what is the reason why cucumbers only bloom but do not bear fruit? Let’s take a look below.

1. Improper fertilization

Cucumber is a plant that has high requirements for fertilizer . If improper fertilization is applied, it will affect its growth and fruiting. Generally speaking, there are several situations where fertilization is inappropriate:

Applying too much compound fertilizer will result in poor root absorption capacity, making it unable to absorb enough water and nutrients, thus affecting growth and fruiting.

Applying too much nitrogen fertilizer will cause the plants to grow too vigorously, with lush stems and leaves, but few flowers and fruits.

Applying too little phosphorus and potassium fertilizers will result in the plant's weak resistance to stress, making it unable to withstand low temperatures, drought, pests and diseases, thus affecting its growth and fruiting.

Solution: Apply compound fertilizer, nitrogen fertilizer, and phosphorus and potassium fertilizers reasonably according to the growth stage and needs of cucumbers. Generally speaking, sufficient base fertilizer should be applied before sowing to ensure nutrient supply during the germination period; nitrogen fertilizer should be appropriately increased during the branching period to promote stem and leaf growth; nitrogen fertilizer should be appropriately reduced during the flowering period and phosphorus and potassium fertilizers should be increased to promote the formation of flowers and fruits; compound fertilizer and phosphorus and potassium fertilizers should be appropriately increased during the fruiting period to ensure the quality and yield of the fruit.

2. Overdosage of pesticides

Pest and disease prevention is an essential task in the cucumber planting process, but if the pesticide is sprayed excessively or irregularly, it will cause pesticide damage, leading to physiological disorders of the cucumber and affecting flowering and fruiting. There are several situations where excessive or irregular spraying of pesticides occurs:

Using pesticides with too high or excessive concentrations will cause irritation or burns to the plants, affecting their normal growth.

Mixing or alternating multiple pesticides can cause the effects of the pesticides to cancel each other out or produce side effects, affecting normal growth.

Spraying pesticides when the temperature is high or the light is strong will cause the plants to be affected by photolysis or phototoxicity, affecting their normal growth.

Solution: When spraying pesticides, strictly follow the dosage, concentration, method and time specified in the instructions. Generally speaking, it is not advisable to spray pesticides when the temperature is below 25℃ or above 35℃, and the light is weaker than 3000 lux or stronger than 10000 lux; before spraying pesticides, a small area test should be conducted to observe whether there is any pesticide damage, and then large-scale application can be carried out; when spraying pesticides, spray evenly to avoid missing or repeated spraying; after spraying pesticides, clean the sprayer, gloves and other tools in time to avoid pesticide residue.

3. Improper watering

Watering is one of the most basic and important tasks in the cucumber planting process. If watering is improper, it will affect the growth and fruiting of cucumbers. Generally speaking, there are several types of improper watering:

Too much or too little watering will lead to inappropriate soil moisture, affecting the respiration and absorption of the root system, thus affecting growth and fruiting.

Inappropriate watering time will lead to excessive temperature changes, affecting the plant's ability to adapt, thereby affecting growth and fruiting.

Improper watering methods can cause leaves or flowers to become wet or washed away, affecting photosynthesis or pollination processes, thereby affecting growth and fruiting.

Solution: According to the soil, climate, season and plant conditions, properly control the amount, timing and method of watering. Generally speaking, water the plants in time when the soil is dry, keeping the soil moist but not waterlogged; water the plants in the morning or evening, and avoid watering them at noon or at night; water the plants along the roots of the plants, and avoid watering directly on the leaves or flowers.

4. Poor pollination

Cucumber is a dioecious plant that needs to be pollinated by wind or insects to produce fruit. If pollination is poor, the cucumber will bloom but not bear fruit. There are several cases of poor pollination:

The imbalance in the ratio of male to female flowers results in the female flowers lacking sufficient pollen sources and being unable to fertilize.

Insufficient wind or insect numbers result in poor pollen transfer between male and female flowers, making fertilization impossible.

Unsuitable temperature or humidity will cause pollen vitality to decrease or become ineffective, making fertilization impossible.

Solution: When planting cucumbers, choose high-quality seeds to ensure a normal ratio of male and female flowers; during the flowering period, provide adequate ventilation or release bees and other pollinating insects to increase the chance of pollination; when the temperature is below 15°C or above 35°C, and the humidity is below 40% or above 80%, take regulatory measures to maintain appropriate temperature and humidity.

That’s it