Why do the ovaries turn yellow in a greenhouse cucumber
They delighted me with a generous harvest from May to September. Imagine my disappointment and disappointment when, at the next visit to the greenhouse, instead of an abundance of crispy greens, I found many yellowed and fallen ovaries.
Determined to find out what happened to my green pets, I went through my country magazine files and strolled through the gardening forums. It turned out that this symptom of general ill-being can hide a number of serious problems, in most cases associated with flaws in the care of greenhouse plants.
Crop rotation is also needed in the greenhouse
The most obvious and easily removable reason for the discharge of ovaries in a cucumber is long-term cultivation in one place. When crop rotation is disturbed, pathogens characteristic of this particular culture accumulate in the greenhouse soil. Plants can no longer successfully withstand the onslaught of external aggressors.
But what about those vegetable growers - cucumber lovers who, like me, use exclusively for planting this mega-popular culture? They come to their aid, that is, the sowing of special plants with phytosanitary properties. Mustard heals and cleans the soil very well in the greenhouse. This wonderful green manure grows quickly, is not afraid of light autumn frosts and saturates the soil with excellent easily digestible organic matter.
Poor soil = poor harvest
When growing cucumbers in one place for many years in a row, the soil is depleted on one side, the same useful elements are taken annually. For the full restoration of fertility, it is no longer necessary to do only the introduction of humus. If just one word "mineral water" makes you frown with displeasure, then I recommend limiting yourself to the usual autumn filling of greenhouse soil.
I, in turn, advise not to give up completely, but to bring them under the siderates. As grass, passing through the digestive tract of a cow, turns into delicious milk, so chemical macro- and microelements, being assimilated by green manure, will return to the soil in an ideal form for absorption by plants.
Cucumbers love stability
The homeland of cucumbers is humid and warm subtropics, which are not characterized by sudden changes in weather conditions. The same stable environment should be strived to create in the greenhouse. Unfortunately, due to employment or other life circumstances, the summer resident does not always manage to provide greenhouse residents with timely watering, loosening and airing.Cucumbers especially do not like interruptions in the flow of moisture during the fruiting phase. A large amount of green mass requires a lot of water, which the superficial root system of the cucumber collects from a shallow depth. Therefore, plants react to insufficient watering with massive yellowing and dropping of ovaries.
Cucumbers love stability
By the way, greenhouse cucumbers require more frequent (up to 5 times a week) and thorough soil moistening than ground cucumbers. This is due to the increased air temperature in the greenhouse. In cool weather, it is better to organize watering in the morning; on sunny days, this work is transferred to the evening. And light refreshing sprinkling will help to relieve the stress of the summer heat.
Prolonged cold snap, when the temperature drops below + 10 ... + 14 degrees Celsius, is even more harmful for thermophilic cucumbers, since in this case their roots completely stop pumping nutrients out of the soil. Because of this, the already set fruits grow slowly, become ugly, and only the blossoming flowers begin to wither and fall off. To make the plants easier to survive difficult times for them, use foliar dressing (spraying) with solutions of complex mineral fertilizers with microelements.
... and do not like tightness
Sometimes, even under the most ideal conditions, the ovaries on greenhouse cucumbers wilt and crumble. In such cases, it is necessary, first of all, to figure out if the plants in the garden are not crowded. If the planting is too tight, the insolation is disturbed, and the cucumbers suffer from poor lighting.
Cucumbers do not like crowding
In this case, the dropping of flowers and wilting of the ovaries is a simple answer to such "Spartan" growing conditions. In addition, a thickened planting is a direct invitation to a cucumber patch of various fungal diseases that quickly spread in the damp stagnant air of the greenhouse.
Unbelievable, but true: some modern cucumber hybrids can simultaneously form up to 150 greens on one bush! Naturally, no amount of fertilization and watering will be able to give the plant enough strength to feed such a colossal crop. Therefore, on such prolific specimens, it is better to remove excess flowers on time, leaving 20-25 ovaries on each separate bush.
Don't Forget Trace Minerals
Another reason provoking the discharge of ovaries in greenhouse cucumbers is an unbalanced diet. Often, the summer resident is overly carried away by one species, completely forgetting that plants need not only phosphorus, potassium and nitrogen, but also a full complex of trace elements.
Cucumbers need micronutrients
But cucumbers need them in very scanty doses: to fill the deficit, it is enough to add micronutrient fertilizer containing molybdenum, boron, copper, zinc, manganese to the greenhouse soil once every 3-4 years. Again, harsh opponents of all kinds of "chemistry" can achieve the same fertilizing effect if they fill the soil in the greenhouse with wood ash annually (at a rate of 250-300 grams per square meter of its area).
Check the pollination quality ...
Of course, growing cucumbers in a greenhouse only means planting parthenocarpic(self-pollinated) varieties and hybrids. However, in this case, plants can throw off the ovary from poor fertilization. This is most often due to stagnant air in the greenhouse (poor ventilation) and too tight planting. Both factors can work at the same time.What can be done to improve the quality if you nevertheless decide to plant your favorite varieties of bee-pollinated cucumbers in the greenhouse?
- Open wide doors and vents in the morning (from 6 to 10) so that bees and other pollinating insects have free access to flowers. To lure these little helpers into the greenhouse, place bowls with sugar yeast syrup... It is prepared very simply: dissolve two parts of sugar in one part of water, add 5% yeast to the mixture and bring to a boil. It is advisable to renew the treat every other day. And to give the sweet mass of cucumber aroma, freshly picked male cucumber flowers are lowered into it so that insects can crawl over them and not get bogged down in syrup.
- Manually pollinate the ovaries... This method is suitable for small greenhouses and for particularly hardworking gardeners.
Bacteriosis is to blame
The development of bacteriosis occurs with excess air humidity in the greenhouse in combination with a thickened planting. This insidious disease causes dropping and yellowing of cucumber ovaries, leading to a sharp decrease in yield.You should start sounding the alarm if you find small shapeless specks on cucumber leaves - this is a signal of a beginning bacteriosis. In wet weather, droplets of a cloudy liquid (bacteria colonies) appear on them. Drying out, the affected areas become thinner and crumble. As a result, the leaves of the plants turn out to be speckled with small holes, and the flowers begin to wither and crumble.
Cucumber bacteriosis. Photo from the site atmagro.ru
Most often, bacteriosis manifests itself in a damp, cool summer. Having found the first signs of the disease, the affected flowers are carefully removed, and the wounds that appear in their place are wiped with a cotton pad moistened with a pale pink solution of potassium permanganate.
To prevent this and other types of rot, plants in the greenhouse are recommended to be regularly sprayed with a 1% solution or a 0.4% solution of a suspension of copper oxychloride.
Thus, observing the rules for caring for greenhouse cucumbers, you are unlikely to encounter yellowing and dropping of ovaries on plants. And in a cold and rainy summer, it is better to prevent such problems - preventive spraying and more frequent and thorough ventilation of the greenhouse will help.