Tomato "Noire de Crimea" (Krymski Chorny)

Tomato "Noire de Crimea" (Black Crimean).
Early tall (indeterminant) variety yielding fruits of about 150-170 g. The variety is appreciated for very tasty fruits of unusual colour.
Seeds are sown in March. For the seeds to germinate quickly and uniformly, the seeding is covered by glass or film.
The temperature of substrate for sowing must be not less than + 21+26°C, room temperature should be not less than +23°C.
When the plants develop 2-4 true leaves, they are transplanted one by one. Seedlings are planted in the greenhouse, when frost is no longer a threat.
Tomatoes are not demanding of soil, but grow best in loam.  0.1 g contains about 20-30 seeds. 0.1 g of seeds will be sufficient to cover the area of 6-8 m2 - high yield, 35 - 50 kg, is expected under favourable growth conditions.

Soil preparation.
When growing vegetables for many years, the soil in the greenhouse gradually deteriorates, and a huge number of pathogens accumulate in it. Therefore, soil preparation must solve two main problems:
1. creating an optimal water-air regime for plant nutrition
2. maximum neutralization of the soil from accumulated infection.
To solve the first problem, a large amount of organic fertilizers is needed. Depending on the crop and the duration of cultivation, 10-20 kg of humus or the same amount of straw with additional mineral fertilizers will be required per 1 m2 (it is best to use wheat straw, the cultivation of which did not use herbicides).
During the season, the straw mineralizes, as a result of which it absorbs a large amount of nitrogen, so at the beginning of the season it is necessary to add 1-2 kg of nitrogen per 1 ton of straw.
The tomato carries a large amount of nutrients with the harvest, so to obtain high yields, it is necessary to apply a sufficient amount of fertilizer. Organic fertilizers for tomatoes are applied at the rate of 10-12 kg of humus per 1 m2 for the main soil treatment, and mineral fertilizers - 70% in the main application and the rest in the form of fertilizing during the growing season.
When straw or high peat is added to the soil, the root layer is enriched with organic matter, and the physical properties of the soil are improved. Fertilizing with fresh manure is undesirable, as this can lead to increased vegetative growth of tomato plants and delayed fruiting. If the soil in the greenhouse is not warmed up well enough, then fruiting of the tomato is delayed by a week or more.
The soil warms up very slowly in the spring, and even when the air temperature in the greenhouse in March in sunny weather reaches +30°C, the soil temperature in the root layer barely reaches +15+16°C, which negatively affects the development of the plant.
A soil temperature favorable for plants allows the formation of ridges to be maintained after digging:
firstly, when ridges form, the area of contact between the soil and warm air increases,
secondly, on the ridges the air capacity of the soil improves (the likelihood of excess moisture decreases)
and thirdly, on the sides of the ridge the soil is heated much faster by warm air than from above.
Timely warming of the soil allows you to avoid a number of diseases associated with root and basal rot.
Simultaneously with improving the structure of the soil, measures for its preparation should solve the second problem associated with the accumulation of infectious background in the greenhouse.
Freezing the soil in a greenhouse in winter only helps in controlling pests (whiteflies, aphids), but does not destroy fungal spores in the soil and on plant debris. Nematodes, overwintering female mites and some other pests also remain unharmed. Today, soil disinfection in a greenhouse can be carried out in different ways: steaming, introducing biological protection agents, etc.
Each of the above methods has its own advantages and disadvantages: steaming destroys all types of pathogens, but this method is quite expensive to use and maintain; chemical disinfection is very effective when used correctly, but it is necessary to treat the soil at least two months before planting; biological means of protection are safe for humans, but operate in a narrow temperature range.
Seedling.
To obtain an early harvest, tomatoes are grown in seedlings, which makes it possible to obtain more even plants with lower heating costs, since the seedling compartment makes up on average 10-15% of the total area of the greenhouse.
Seedlings for film greenhouses with heating begin to be grown in the second half of January, and without heating - in the second half of February.
Tomato seedlings are grown in pots or cassettes: seeds are sown to a depth of 0.5-1 cm in boxes or cassettes filled with a nutrient mixture. To get friendly, uniform shoots, sprinkle the seeds on top with a thin layer of light porous material (perlite, peat, vermiculite).
For successful seed germination, it is necessary to maintain the soil temperature around +23+24°C around the clock. After the emergence of seedlings, the air temperature during the day should be at +22+23°C with additional lighting turned on.
When sowing in boxes, after 12-14 days the resulting seedlings are planted in pots with peat or turf soil, and weak plants are simultaneously discarded. Picking must be carried out in a well-moistened, warm substrate (+18+20°C). The optimal size of a tomato seedling pot is 0.6-0.8 liters.
Hardening off seedlings is an optional technique, since in this case the start date of tomato fruiting is delayed by 10-14 days, but the seedlings are more resistant to unfavorable environmental conditions. This technique is only necessary when planting tomatoes in unheated greenhouses, when the likelihood of frost after planting seedlings is high. Hardening off seedlings is carried out in order to reduce the risk of damage to the plant by low temperatures.
Plant nutrition.
When growing a tomato crop in a short rotation (to obtain the first 6-7 bunches), it is enough to add humus and mineral fertilizers to the main dressing when preparing the soil, but the quality of the resulting product will not be high. As a rule, cheap and poorly water-soluble fertilizers are added to the main dressing: superphosphate, nitroammophosphate, etc.
The effectiveness of such fertilizers is low and extended over time. Once in moist soil, fertilizers begin to gradually dissolve, increasing the concentration of salts, although this is not always necessary for young plants. During the process of growth, plants remove from the soil the nutrients necessary for their development and over time the concentration of salts in the soil decreases. As a rule, this happens during the period of maximum plant load (flowering of the seventh cluster).
In such conditions, the fruits on the first 2-3 clusters fill very intensively, but the upper ones lack nutritional elements, the flowers are dropped, the fruits on the upper clusters are poorly set and shredded. Such fruits do not reach their optimal weight by the time of harvest. To avoid such a situation, the agronomist needs to carry out regular root feeding. Drip irrigation copes best with this task.
Drip irrigation is necessary for the gradual, timely and uniform application of fertilizers and water directly into the root zone. To obtain a higher yield and very high quality products, additional costs are required for water-soluble fertilizers, which can be applied with drip irrigation. Today, there are many companies producing such fertilizers with different contents of macro- and microelements.
The basic requirements for fertilizers used for drip irrigation are the following: complete solubility in water (without sediment at a temperature of +20°C), maximum content of active substance, balanced nutrition, reasonable price.
It is quite easy for agrochemists to create the solution needed to feed tomato plants from simple or complex water-soluble fertilizers; they only need to know the optimal ratio of nutrients in different phases of plant development.
Hardening is carried out in two stages: first, the seedlings are hardened, and then the seedlings. The air temperature for 5-7 days after the emergence of seedlings is maintained at +13+15°C during the day, and +7+9°C at night. The soil temperature should not fall below +12+14°C.
After hardening the seedlings, before hardening the seedlings, the temperature is maintained at +21+23°C (on a sunny day), +17+19°C (on a cloudy day), and at night +10+12°C.
Seedlings are hardened at a temperature not lower than +10+12°C during the day and +4+5°C at night.
Planting.
Ready tomato seedlings must be balanced in terms of generative and vegetative development of plants.
A normal plant at the beginning of cultivation should meet the following characteristics: there should be 9-10 leaves under the first flower cluster; brush of regular shape with a short stalk; internodes 5-7 cm long; the root system should envelop the entire pot and the substrate should not crumble when removed from it; plants should have a rich green color.
Watering seedlings should be stopped at least 24 hours before planting, as watering before transport from the seedling compartment can lead to brittleness of the plants and the risk of damage. To avoid contact of the root collar with the soil, seedling pots must be placed in the greenhouse soil so that they protrude 1-2 cm above its surface. The average planting density of hybrids is 2.2-2.5 plants per 1 m2.
The age of seedlings greatly depends on the zone and conditions of tomato growing. For heated film greenhouses, the age of seedlings can vary between 35-45 days, and for unheated greenhouses - 50-60 days. This increase in the seedling period for unheated greenhouses when sowing at the same time is associated with the temperature regime in the seedling compartment. After planting in a permanent place, the temperature regime depends on the level of illumination, since on cloudy days in the greenhouse it is necessary to maintain the air temperature at +20°C during the day and +17°C at night, on sunny days - +22°C and +18°, respectively WITH.
Planting scheme: in the row between plants the distance is 50-55 cm, and between the rows - 80 cm; for paired rows - 70 x 90 cm (where 90 cm is the row spacing for harvesting products and caring for plants). Seedlings are planted in a checkerboard pattern.
Fruit growth.
From the moment of fruit set to harvest in spring, 55-60 days pass.
Optimal conditions for the pollination process are temperatures up to +2 °C and humidity 65-75%.
Pollination can be done in the following ways:
• using bumblebees
• using mechanical vibrators
• using hormones.
Plant care.
Forming plants into one stem with the removal of side shoots allows you to obtain high-quality products with a high yield of standard fruits. When growing a sloping tomato, you can leave up to 18 leaves on the plant in spring and up to 24 in summer. At one time it is necessary to remove no more than 2-3 leaves. Leaves must be removed completely, without leaving “stumps” on the plant. Removing leaves helps to better ventilate the plants, which means reducing the risk of fungal diseases, as well as stimulating fruit ripening.
Leaves must be removed weekly, preferably in sunny weather. Wrapping the tops of plants is best done in the afternoon, when the plants lose turgor and the likelihood of plant breakage is reduced. Just like removing leaves, turning the tops clockwise should be done weekly. It is necessary to pinch the tops of the main stem 40-50 days before eliminating the crop; in this case, you can get large fruits from the upper clusters. During the entire growing season, it is necessary to systematically remove side shoots (stepchildren) with a length of no more than 5-7 cm, since their strong growth leads to significant yield losses.
To ensure a uniform supply of high-quality products, it is necessary to standardize the fruits on each cluster. A very high yield of standard products ensures that 5-6 fruits are left in the bunch. The best taste and high keeping quality are observed when the fruit is harvested in its ripe (red) form.
Climatic factors.
Regulation of the microclimate in the greenhouse should ensure changes in the vegetative/generative growth of plants.
Strong generative growth very quickly exhausts plants, and strong vegetative growth leads to delayed flowering and fruiting.
The main factor determining the microclimate is the light intensity: the higher the solar radiation, the higher the air temperature should be.
An important microclimate factor is relative air humidity. Its optimal range for tomato is 70-75%. The main criterion for regulating air humidity is the presence of dew on plants and fruits. As a rule, the critical period when dew is most likely to fall on plants is the period of sunrise, so 1-2 hours before this it is necessary to warm up the plants in the greenhouse and carefully monitor ventilation.
Remember an important rule: the air temperature in the greenhouse can drop sharply, but in no case should it be allowed to rise sharply.
Watering.
To water tomatoes, you should use water with a low salt content, which is especially important for drip irrigation. Depending on the type and volume of substrate used, the tomato watering strategy changes. In greenhouses without drip irrigation, watering is carried out from hoses at varying frequencies: from once a month to 3-4 times a week, depending on the phase of plant development, soil moisture and other factors.
Watering is carried out taking into account evaporation, solar radiation, soil structure, crop condition, ventilation, etc. For irrigation, you should always use water with a temperature of +15+16°C and above.
The disadvantage of this method of irrigation is the high cost of manual labor and the unevenness of the amount of water used, which makes it difficult to manage plants. With drip irrigation, the task of managing the plant is easier: you can give it the required amount of water at any time and maintain the required ratio of nutrients.
The daily volume of watering depends on the substrate: the daily dose of the solution can range from 0.2 to 4 liters per plant. The optimal soil moisture for the most intensive plant growth is 70-80% of total moisture capacity. In the process of growth and development, tomato plants need a certain ratio of nutrients, which can be applied in the form of fertilizing. In the initial period, to form a good vegetative mass, tomato needs fertilizing with nitrogen fertilizers.
In the future, during the formation of fruits and their intensive filling, plants require an increased potassium content. It must be applied during the growing season in the form of fertilizing. A lack of potassium leads to slower ripening, decreased fruit quality, and increased sensitivity of plants to fungal diseases. When sowing early during periods of prolonged cloudy weather, it is necessary to increase the potassium level and bring the N:K ratio to 1:2.
We must also not forget about feeding phosphorus fertilizers during the initial period of plant development, since phosphorus promotes better development of the root system, accelerates flowering and fruit ripening. Phosphorus is very poorly absorbed by plants at low soil temperatures; on plants this manifests itself in the form of anthocyanin coloring on the underside of the leaf.
During any growing period, cracking of tomato fruits is possible. In most cases, it is caused by rapid temperature changes, especially in the morning against the background of high soil moisture. Ring cracking around the stalk occurs when the temperature in the greenhouse rapidly increases and there is insufficient ventilation, which leads to moisture condensation on cold fruits. Longitudinal cracking is associated with high root pressure in the morning and poor fruit growth at this time due to low temperatures.
During the day, plants' consumption of water (fertilizer solution) increases with increasing light intensity. It is best to start watering 1-2 hours after sunrise and avoid evening watering, which can also cause various diseases. It is necessary to finish watering 2-3 hours before sunset. Peak consumption of the solution occurs at 12-14 hours of the day. When using drip irrigation, the daily watering rate should be divided into doses and given to plants in parts with a maximum frequency between 11:00 and 14:00. With this type of watering, plants will use water and applied fertilizers most efficiently.
Controlling plant growth.
To obtain maximum yield, it is necessary to constantly monitor the development of plants and maintain a balance between vegetative and generative growth.