by Before you had time to rejoice at the abundance of ovaries on the cucumber bushes, they began to dry out, turn yellow and fall off one after another. The enviable harvest and winter supplies were suddenly under threat. What could be the reason and how to deal with it – we will figure it out in this article.
Often cucumber vines, covered with many ovaries, suddenly begin to lose future fruits – they turn yellow, dry up and fall off in a short time, leaving us without hope for a rich harvest. In what cases can this happen, what mistakes in care lead to the ovaries falling off and what can be done to save the harvest?
Lack of light
Problems with fruiting (few flowers and ovaries, their falling off) are often associated with insufficient lighting of plantings. This is especially true for cucumbers grown in a greenhouse, but such a situation can also arise in open beds located in a shaded area of the plot. At the same time, cucumbers are one of the most demanding crops for lighting; for normal development and fruiting, they need at least 12-14 hours of light per day.
Excessive shading of plantings can also be caused by:
- dense planting of cucumbers in a greenhouse or garden bed, combining this crop with others that are taller or faster growing;
- absence of pinching and shaping of shoots, which as a result promotes the growth of lateral shoots;
- incorrect placement of the greenhouse or garden bed in relation to the cardinal directions.
When installing a greenhouse, consider the recommendations for your region: for the north and middle zone, placement from east to west is considered correct, for southern latitudes – from north to south.
To provide cucumbers with good lighting, it is important to leave enough space for each plant when planting seedlings: it is customary to place 1-1 bushes of parthenocarpic hybrids or 2-2 plants of bee-pollinated varieties per 3 sq. m of area.
Don’t forget to pinch the tops of the shoots and form the vines – you can learn all the details and rules from this article. For combined planting with cucumbers, choose the right “neighbors” – those that will not outgrow and compete with the main crop.
Temperature changes
Cucumbers grow and develop best at stable, moderately warm temperatures:
- 20-24°C during the day and 17-18°C at night – until fruiting begins;
- 21-26°C during the day and 18-20°C at night – during the period of active fruit setting and ripening.
Sharp temperature changes in any direction are dangerous because of the slowdown in the growth of the cucumber plant, dropping of ovaries, drying out or burns on the leaves. At the same time, such temperature swings are not uncommon for cucumbers growing in a greenhouse: during the day in hot sunny weather, the thermometer inside the greenhouse can show up to 35-40 ° C, and nights in a moderate climate are often cool even in the middle of summer. And even in open beds, the cucumber plant often suffers from climatic “surprises”.
To prevent excessive temperature fluctuations, it is recommended to cover the greenhouse with a shading net or spray it with a chalk solution (2 kg of chalk and 400 ml of milk per 10 l of water) in hot weather. Regular ventilation of the greenhouse should also be organized – for this purpose, an automatic drive with temperature sensors can be installed on the vents and doors.
Open ground plantings are also shaded with light agrofibre or netting to protect them from the sun; in hot weather, they are watered early in the morning or in the evening, mulched, and when it gets cold, the beds are covered with film at night or dark spunbond is laid on the soil.
Nutrient Deficiency
The ovaries may turn yellow and fall off in adult fruit-bearing bushes when the soil’s nutrient reserves are depleted. In this case, cucumbers are capable of setting many fruits (this is especially true for high-yielding parthenocarpic hybrids), but the lack of nutrition does not allow them to fill out and ripen – and the plants shed the “unbearable” surplus.
Since cucumbers are one of the most “voracious” vegetable crops, timely fertilizing – both organic and mineral – is extremely important for their active and long-term fruiting. Even during preparation in the fall, the bed is filled with manure, and green manure is sown on it.
During the growing season, cucumbers begin to be fed already at the seedling stage, and after planting in the ground, specialized complex fertilizers (Agricola, Rastvorin, Master, Fertika Kristalon) and organic fertilizers continue to be regularly added. For example, ash can be incorporated into the soil in dry form at the rate of 300 g per 1 sq. m or added to a urea solution (1 tbsp. urea and 3 tbsp. ash per 10 liters of water).
Watering errors
Proper watering of cucumbers in a greenhouse and in open ground is no less important than sufficient light. Lack of moisture is one of the common reasons for drying out and falling off of ovaries, so it is necessary to observe the “drinking regime”.
- At the first stage of vegetation, before flowering and fruiting, it is recommended to water cucumbers twice a week, using approximately 4-5 liters of water per 1 sq.m.
- During the flowering and active fruit setting period, cucumbers are watered three times a week, and the volume of water for each watering is also increased – up to 8-12 liters per 1 sq.m.
- By the end of fruiting, from mid-August until the end of the season, the frequency and volume of watering are reduced – once every 10 days and 3-4 liters per 1 sq.m. is enough.
In hot weather, cucumbers should be watered every day, since the soil, especially without mulch, dries out quickly. In case of rainy or cool weather, the amount of watering is reduced, since excess moisture also negatively affects the condition of cucumber plantings – in both cases, the plants can shed their ovaries.
It is critically important to use settled, non-cold water for watering. Cucumbers respond best to a water temperature of 22-25°C, but watering with cold water on hot soil will certainly lead to the ovaries falling off.
Cucumber diseases
Yellowing of ovaries can be a symptom of a dangerous disease – angular leaf spot, or cucumber bacteriosis. The disease occurs due to increased soil and air humidity, and is aggravated by temperature changes and lack of normal aeration with dense planting.
The second characteristic sign of bacteriosis is shapeless light spots on the leaves, which eventually turn brown and dry out, leaving holes in the leaf blades in their place. With mass infection, the cucumber sheds more than half of all ovaries.
To prevent bacterial and other infections, it is recommended to treat greenhouses with sulfur checkers in the fall (Climate, Fas). Preventive spraying of plantings with Bordeaux mixture (1% solution) or preparations based on copper oxychloride (Abiga-Peak, HOM) is also effective. Biofungicides (Gamair, Trichoderma Veride 471) or Farmayod-3 can be used to treat diseased plants.
Poor pollination
Despite the fact that many gardeners have recently given preference to parthenocarpic cucumber hybrids, bee-pollinated varieties still remain popular. In order for fruits to form on such plants, pollination by insects is necessary. If bees and bumblebees are rare guests on your plot, then many female flowers on cucumber vines may remain unpollinated and will soon fall off.
To attract insects to cucumber beds, spray with a sweet solution: 1 tbsp. sugar or honey per 1 liter of water. Treat the flowering bushes and expect winged guests soon. Try not to scare them away with the aroma of smoke – arrange a barbecue area away from the garden.
To avoid such a problem in the future, choose only parthenocarpic cucumbers for growing in closed ground, which do not require pollination. By the way, bee-pollinated plants can be helped by pollinating the flowers manually.
There are many reasons why cucumbers may drop ovaries, as well as ways to help the plants. Solve problems as they arise, armed with knowledge. And if you want to double your harvest, study our material on this topic.
