Why is barren flowers formed on tomatoes in a greenhouse
Nether flowers on tomatoes in a greenhouse are always an unpleasant situation for a gardener. Before saving the plant, you need to find out the reasons for this problem.
Tatiana Orlova (Candidate of Agricultural Sciences):
Actually, nature is so programmed from the beginning that not all of the resulting flowers are pollinated and bear fruit. Therefore, the number of flowers is laid on the plants with a larger supply than the plant itself can "feed" the fruits. The fact that some of the flowers fell off without setting the fruit should not cause alarm. The inflorescence of a tomato is called a brush. This brush can be simple or complex and the number of flowers in a brush is from 4-5 to 12-15 pieces. But after flowering, usually from 1 to 3-5 fruits are formed in the brush. If the fruits are also large-fruited, but the leg of the brush simply would not bear their weight and broke off
Reasons for the formation of barren flowers in the greenhouse
Signs of barren flowers on tomatoes
It can be identified at the stage of fruit setting, because there are many flowers on the tomato, but they all fall off, and the plant remains empty. One tomato has several flowers at once (up to 10).
Causes
In the greenhouse, barren flowers are observed more often than in the open field.
Access to pollinators, lack of crop rotation, irrigation and access to sunlight is limited. This makes the planting site and grooming process better organized.
Why barren flowers form on greenhouse tomatoes:
- Temperature. Tomato flowers can only be pollinated in warm weather. It should not fall below 15˚С at night, and below 25˚С during the day.
- Humidity. The comfort level is in the 40-70% range.
- Sunlight. Tomatoes are light-loving plants, they need access to the sun's rays all day.
- Pollinators. Tomatoes are pollinated by insects, the presence of wind and or draft is important.
- Fertilizing and feeding. The wrong amount of fertilizer and the growth stage is a problem. An excess leads to fattening of tomatoes, and a deficiency leads to a small yield.
- Seed selection. If you collect seeds from your tomatoes, then after a few years, yields are significantly reduced.
- Diseases.
- Pesticides. Abuse of these substances adversely affects the reproductive qualities of the vegetable.
Tatiana Orlova (Candidate of Agricultural Sciences):
The most common reason for the lack of pollination of tomato flowers is a sharp fluctuation in temperature (from too low to high and vice versa during the flowering time). Therefore, it often happens that in the first cluster the fruits set well, and in the second and subsequent fruits there were few or no fruits at all.
Ways to prevent the appearance of barren flowers
If the tomatoes in the greenhouse bloom profusely, but the ovary is formed a little, then you need to urgently take action. The simplest thing is to break off the extra flowers, so the tomato will be able to distribute its strength among the remaining ones. Better to leave 3-4 pieces per plant.
Temperature
To prevent the temperature from dropping in greenhouses, they are closed overnight.If during the day the air does not warm up enough to the prescribed 25 ° C, then the greenhouse is opened for a couple of hours in the middle of the day. It is also allowed to use felt materials or mats, but this will not help with a sharp cold snap.
Tatiana Orlova (Candidate of Agricultural Sciences):
It is more difficult to lower the temperature in the greenhouse because it is the high temperature (above +30 degrees) that causes the sterility of tomato pollen. Shading the greenhouse in different ways - whitening, covering with a white non-woven material, shading nets, simultaneously with a decrease in temperature, reduces the illumination and the tomatoes begin to stretch. In large greenhouse plants, along with heating in the cold season, air conditioning of premises with vegetables is also provided.
Humidity
Humidity is much more difficult to control. The soil in plants should not be allowed to dry out, but the air should not be too dry. In order to raise the humidity level, it is enough to spray the tomato bushes with water or a light fertilizer solution.
Moisture is important for the formation of ovaries
It is advisable to do root watering (each bush separately, at the very root). Drip irrigation will be a good solution for the gardener - this way moisture flows slowly and water is saved. Do not water with cold water, because tomatoes can shed their flowers from such stress.
sunlight
For maximum enrichment with the sun's rays, you need to think in advance about a place for building a greenhouse. It should be a flat or small hill, without tall trees and buildings nearby. Such a greenhouse is not covered with agrofibre.
Pollination
Vegetables are pollinated by insects, but with the obligatory presence of air currents (wind or draft is needed). To organize it, the door and window are opened during the day for ventilation (ideally, this should be done opposite each other for better air circulation).
Fertilizer
It is important to maintain a balance in fertilization and feeding. To prevent tomatoes from fattening, it is necessary to reduce nitrogen fertilization at the stage of growth of the plant itself. During the flowering period, tomatoes need additional feeding, do not forget about this when the ovary forms.
- Before the formation of the ovary, fertilize with a solution of 80 grams of superphosphate, 30 grams of nitrate, 25 grams of potassium per 10 liters of water and pour under the root of each plant.
- When the fruits have formed (until ripening), a mixture is used in which 40 grams of superphosphate and 30 grams of potassium are dissolved in 10 liters of water.
- After fertilization, the plants must be watered to avoid scalding the roots and stems.
Tatiana Orlova (Candidate of Agricultural Sciences):
At the time of flowering, all fruits (and tomatoes too) must be provided with such a trace element as boron. The lack of boron during the laying of the reproductive organs affects both the intensity of flowering and fruit formation. If you often meet with unsatisfactory tomato flowering on your site, perhaps there is not enough boron in the soil. Carry out foliar (on the leaves) application of boron fertilizers, for example, Mag-boron, Boro-plus or Ultramag Bor.
Diseases
Diseases, especially viral ones, not only affect the leaves and roots, but also the set fruits. Spotted wilting, streak, cucumber mosaic, columnar, tobacco mosaic should be destroyed as soon as it was discovered. It is better to remove infected bushes, so the rest of the planting will be saved.
Do not use illegal drugs such as pesticides. They are not only harmful to the human body, but also have a bad effect on tomatoes.
In this case, substances containing plant hormones will be an excellent option. They can help in situations where it is impossible to control the parameters of humidity and temperature (sudden cold snap, cloudy weather).
It is allowed to select seeds from one site no more than 1-2 times, then hybrid varieties "get tired" and cannot give large yields.
Prophylaxis
In order to avoid empty flowers on tomatoes, you need to do the following:
- Install a thermometer and hygrometer in the greenhouse. In this way, the parameters of the air are determined more accurately, and you can start the fight against barren flowers in time.
- When planting, observe the distance: 45-50 cm between tomatoes, 60-65 cm between beds.
- After planting, mulch. Sprinkle at the root with tyrsa or other suitable material - this will not allow moisture to quickly evaporate.
- Choose the right variety.
- Use automation in planting care, namely, automatic water supply when humidity drops, opening vents at high temperatures.
Conclusion
Errors in planting and caring for tomatoes in a greenhouse cause barren flowers. To avoid this, do not forget about the methods of prevention and the basic rules of watering, fertilizing, weeding and harvesting. The result depends only on your efforts.
