Why is a netflower formed on tomatoes in a greenhouse?

An empty flower on a tomato in a greenhouse is always an unpleasant situation for a gardener. Before saving the plant, you need to find out the causes of this problem.

Table of Contents
  1. Tomato flowers
  2. Causes
  3. Ways to prevent the emergence of empty flowers
  4. Temperature
  5. Humidity
  6. Sunlight
  7. Pollination <
  8. Fertilizer <
  9. Disease
  10. Prevention
  11. Conclusion

Tatyana Orlova (Candidate of Agricultural Sciences):

In fact, it was originally programmed by nature so that not all of the pollinated flowers and give fruit. Therefore, the number of flowers with a larger supply than the plant itself can feed the fruit is laid on. The fact that part of the flowers showered without tying the fruits should not cause anxiety. The tomato inflorescence is called a brush. This brush can be simple and complex and the number of flowers in the brush is from 4-5 to 12-15 pieces. But after flowering, usually 1 to 3-5 fruits are formed in the brush.If the fruits are also large-fruited, but the leg of the brush simply could not withstand their weight and broke off

Причины образования пустоцвета в теплице

Reasons for the formation of a hollowflower in a greenhouse

Signs of a hollowflower on tomatoes

You can identify it at the fruit setting stage, because the flowers on there are many tomatoes, but they all fall, and the plant remains empty. Several flowers are located on one tomato at once (up to 10).


In the greenhouse, the barren flower is observed more often than on open ground.

Access to pollinators, lack of crop rotation, irrigation and access to sunlight are limited. This makes it better to arrange a planting place and a care process.

Why empty flowers form on greenhouse tomatoes:

  1. Temperature. Tomato flowers can be pollinated only in warm weather. It should not fall at night below 15 ° C, and during the day below 25 ° C.
  2. Humidity. A comfortable level is in the range of 40-70%.
  3. Sunlight. Tomatoes are light-loving plants, they need access to the sun’s rays all day.
  4. Pollinators. Tomatoes are pollinated by insects, the presence of wind and or draft is important.
  5. Fertilizer and top dressing. The wrong amount of fertilizer and the growth phase threatens with problems. Excess leads to fatliquoring of tomatoes, and the disadvantage leads to a small crop.
  6. Seed selection.If you collect seeds from your tomato, then after a few years, yields are significantly reduced.
  7. Diseases.
  8. Pesticides. The abuse of these substances has a bad effect on the reproductive qualities of the vegetable.

Tatyana Orlova (candidate of agricultural sciences):

The most common reason for the absence pollination of tomato flowers is a sharp fluctuation in temperature (from too low to high and vice versa during flowering time). Therefore, it often happens that in the first brush the fruits tied well, and in the second and subsequent fruits there were few or none at all.

Ways to prevent the appearance of empty flowers

If the tomatoes in the greenhouse bloom profusely, but the ovaries form a little, then urgent measures must be taken. The simplest thing is to break off the extra flowers, so the tomato can distribute its forces between the remaining ones. It is better to leave 3-4 pieces on one plant.


So that the temperature does not drop in the greenhouses, they are closed for the night. If during the day the air does not warm enough to the required 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, however this will not help with a sharp cooling.

Tatyana 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. The shade of the greenhouse in different ways, whitening, shelter with white non-woven material, stitched nets at the same time as the temperature decreases, reduces illumination and the tomatoes begin to stretch. In large greenhouse plants, along with heating in the cold season, air conditioning is also provided for vegetables.


Humidity is much more difficult to control. Drying of the soil in plants should not be allowed, but the air should not be too dry. To raise the humidity level, it is enough to spray tomato bushes with water or a light fertilizer solution.

Влажность важна для образования завязей

Humidity is important for the formation of ovaries

It is advisable to do root watering (each bush separately, under the root). A good solution for the gardener will be drip irrigation – so moisture comes in slowly and water is saved. You can not water it with cold water, because tomatoes can drop flowers from such stress.


To maximize the enrichment of the sun’s rays, you need to think in advance about the place to build the greenhouse. It should be a plain or a small hill, without tall trees and buildings nearby. Such a greenhouse is not covered with agrofibre.


Vegetables are pollinated by insects, but with the obligatory presence of air currents (wind or draft is needed). To organize it, open the door and the window for ventilation during the day (ideally, this should be done opposite each other for better air circulation).


In fertilizer and fertilizing it is important to maintain a balance. To prevent the tomatoes from fattening, it is necessary to reduce nitrogen fertilizers at the stage of growth of the plant itself. During flowering, tomatoes need additional top dressing, do not forget about it when the ovary is formed.

  1. 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 add under the root of each plant.
  2. When the fruits have formed (before ripening), use a mixture in which 40 grams of superphosphate and 30 grams of potassium are dissolved in 10 liters of water.
  3. After fertilizing the plants, be sure to watered to avoid root and stem burns.

Tatyana Orlova (Ph.D. S.-kh.Sciences):

At the time of flowering, all fruits (and tomatoes, too) must be provided with such a trace element as boron. A lack of boron during the laying of the reproductive organs affects both the intensity of flowering and fruit formation. If you often encounter unsatisfactory tomato flowering at your site, there may be a lack of boron in the soil. Perform foliar (leaf) application of boron-containing fertilizers, for example Magbor, Boro-plus or Ultramag Bor.


Diseases, especially viral, not only the leaves and roots are affected, but also the fruit that has started. Spotted wilting, strick, cucumber mosaic, columnar, tobacco mosaic should be destroyed immediately, as it was discovered. Better to remove infected bushes, so the rest of the plantation will be saved.


You can not use illegal drugs, such as pesticides. They are not only harmful to the human body, but also badly affect 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 (unexpected cooling, cloudy weather).

It is allowed to select seeds from one section no more than 1-2 times, then hybrid varieties “get tired” and can’t produce large crops.


so as not to there were empty flowers on tomatoes, you need to perform the following steps:

  1. Install a thermometer and a hygrometer in the greenhouse. So, air parameters are determined more precisely, and you can start the fight against empty flowers in time.
  2. When planting, observe the distance: 45-50 cm between the tomatoes, 60-65 cm between the beds.
  3. After planting mulching.Sprinkle at the root with tyrsa or other suitable material – this will not allow moisture to evaporate quickly.
  4. Choose the right variety.
  5. Use automation in the care of plantings, namely, the automatic supply of water with a decrease in humidity , opening the window leaves at high temperature.


Errors when planting and leaving in the greenhouse in a tomato cause the appearance of empty 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.

Anna Evans

Author ✓ Farmer

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