Seedlings of tomatoes turn yellow leaves what to do. Why tomato leaves turn yellow, and what to do to fix the problem. Yellowing of tomato leaves from lack or excess of nutrients

The garden in the country begins with tomatoes. Everyone's favorite and most common crop that can be grown with your own hands from seed to harvest. Growing seedlings does not require much effort, but sometimes, even yesterday, a green and cheerful tomato seedling suddenly fades, the lower leaves begin to turn yellow or wither, become covered with yellow spots. The seedlings are sick, and the reasons may be different. They can be divided into separate groups: soil, environment, nutrition, watering, diseases, feeding, etc. By analyzing the cultivation process from sowing to disease, it is possible to establish the cause and eliminate it.

The soil mixture is dense, when watering, it floats into a heavy lump. Properly prepared soil consists of humus, sand, peat, turf or forest land. Instead of the last two components, when preparing a soil mixture for sowing seeds, you can take the soil from the garden, where no protection chemicals were used. It is necessary to replace the soil with a properly prepared substrate, transplant the plant. Pierce the soil along the edge of the planting container with a fork or a pointed stick to the bottom so that air can penetrate inside.

Stagnant moisture

Abundant watering with stagnant water causes root suffocation. The root system of plants lacks oxygen. Stop watering until the soil layer dries up to ¾ of the height of the container or to a depth of an outstretched finger. You can generally transplant the plant into another free container and during the first days slightly moisten the plant with fine spraying (as needed). When transplanting, remove diseased roots. Dip the roots in the root solution before planting.

Insufficient watering

Seedlings simply lack moisture in overdried soil. It is enough just to water the plants with warm, settled water.

Unsuitable temperature conditions

For tomatoes, the temperature regime of the soil is very important. After the emergence of seedlings and up to 2 weeks of age, the soil temperature during the day should be + 18-20 ° С, at night + 15 ° С. In the next 2-3 weeks, the temperature remains the same during the day, and at night it is necessary to reduce it to + 12-13 ° C. If there are few seedlings, pallets with pots are removed overnight in a cool place.

Proper watering is very important for tomato seedlings.

Environment

During the day, in the first 10 days after germination, the air temperature is + 15-17 ° С, and at night + 8-10 ° С. It is necessary to ventilate the room in order to reduce the temperature, it is advisable to remove the seedlings from the draft at this time. For the night, rearrange the seedlings in a cool place. 15-20 days before planting in open ground, a seedling hardening procedure is required. The stress state after planting in open ground, caused by a change in environmental conditions, will entail a long-term painful state of the plants, which will be expressed in yellowing of the leaves, along with other signs.

Insufficient lighting

Tomatoes are light-lovers. With a lack of lighting, a long period of cloudy days reduces the activity of photosynthesis of leaves, they begin to turn yellow. Additional lighting is required.

Insufficient air humidity

Dry air causes the entire plant to wilt and / or yellow leaves. It is necessary to remove plants from hot batteries, where the air is always drier. Spray plants with a fine spray bottle. Reception will increase the humidity of the air and give additional moisture to the vegetative mass of plants.

Other reasons

Yellowing of the lower leaves can be observed when growing seedlings in containers that are too small in volume, with poor-quality picking, mechanical damage to the roots when loosening plants after watering and other physical reasons.

Nutrient provision

A properly prepared and fertilized soil mixture should provide 80-90% of the growing seedlings with nutrients. With their lack or oversaturation of the soil with nutrients, the plants look equally oppressed. You can determine which element is missing by the color of the leaves.

• On a poor substrate, the plants are thin, overgrown, with transparent green leaves and stems. It is necessary to feed with a complete mineral fertilizer, preferably a complex one, in which all elements are in an optimal ratio (nitroammofoska, nitrofos, kemira-universal, crystallin, crystallon). The last 3 types of fertilizers contain boron, zinc, manganese, magnesium, molybdenum.
• With a lack of nitrogen, the leaves become covered with yellow spots, acquire a light green with a grayish tinge, the color of the leaf blades, with an excess of plants, intensely green, fatty, but friable. It is enough to feed with a solution of urea or saltpeter.

• With a lack of phosphorus, the top of the leaves turns yellow, the leaf blade along the veins and stems take on a blue-violet or violet-bronze hue (not to be confused with a varietal trait or exposure to cold when the room temperature drops). With an excess of phosphorus, the entire leaf is intensely yellow. Introduce a teaspoon of superphosphate under adult seedlings and water the plants or feed with a superphosphate extract (root, foliar).
• With a lack of potassium, the edge of the leaves is covered with a brown border, and the leaves roll up into a tube. The leaf blade acquires a violet-blue tint. It is best to add wood ash under each plant.
• Plants are depressed if there is a lack of other elements in the soil, incl. microelements (magnesium, calcium, boron, copper, iron, sulfur, etc.). The leaves take on a yellow-green mosaic color. Foliar top dressing with a ready-made composition of trace elements (buy in a store, see the composition) will correct the condition of the plants. You can spray the plants with a solution of kemira, which also contains trace elements. The concentration of solutions is not more than 0.1-0.05%.

External manifestations of the lack of a separate element can be traced by individual characteristics. You can limit yourself to feeding with the appropriate fertilizer.

Timely top dressing helps the plants to recover and subsequently form a fairly high quality crop.

Diagnostics of diseases with yellowing of leaves

Like other vegetable crops, tomato seedlings are susceptible to diseases if the cultivation technology is violated. Most often these are fungal diseases (root rot, fusarium wilting, brown leaf spot, etc.). Some diseases are externally manifested by a characteristic change in the color of the leaves.

• Fusarium damage to plants (popularly called simply yellowing) externally manifests itself in the yellowing of the leaves, which is simultaneously accompanied by their lethargy (subject to normal watering). Even with an unclear etiology, in order to prevent the disease, plants need to be treated with biofungicides (phytosporin, bactofit, phyto-doctor, phytocide, planriz, and the soil is also treated with the latter) 2-3 times a month.
• Brown leaf spot starts from the lower tier. On the upper side of the leaf blades, yellowish spots appear, and on the lower side, a delicate olive bloom of mycelium. Over time, the leaves turn brown, dry out and fall off. For prophylactic and therapeutic purposes, diseased plants are sprayed with the same biofungicides as against fusarium. Can be used for plant treatments with 1% Bordeaux liquid. The procedures are repeated 2-3 times after 7-12 days.

In order for the seedlings to grow healthy, it is necessary, despite their healthy appearance, to be sprayed with biofungicides, which will increase the general immunity of plants to diseases of various natures.

There are several main reasons why tomato seedlings suddenly begin to turn yellow. If you understand each situation, find out the main reasons, it will be much easier to deal with the problem.

The reasons for the appearance of yellowness:

The first thing that needs to be done to prevent the appearance of yellowness on the leaves is to create the necessary conditions for the growth and development of seedlings. So, here it is important to choose the right soil, maintain a suitable level of lighting and humidity. Do not forget about regular watering and feeding with nitrogen, iron and zinc. Pay attention to the choice of a container for disembarkation: the container must have suitable dimensions and a drainage hole for water to drain off - the liquid must not stagnate.

If the soil is wet all the time, the roots of the plant will simply start to rot. The most important thing is to maintain the required temperature regime. The most favorable regime is about 25 degrees Celsius. Also, don't forget that you love moisture. This makes caring for tomatoes quite a delicate process. Make sure that the soil does not dry out, but it is not too wet.

Proper feeding of tomato seedlings will avoid yellowness and other problems that can lead to death and. The first time we feed the plants after the emergence of shoots - literally in 7-10 days. The next time is in another two weeks. For feeding, you can use special means for tomato seedlings, or you can prepare the mixture yourself: we take 10 liters of water, dissolve 35 g of superphosphate and 5 g of urea in it.

It is forbidden to use any type of dressing on a dry earth coma. This can lead to burns on the roots of plants, and therefore always need to moisten the soil.

Problems with yellowness can also be caused by a lack of oxygen in the root system: as a result of watering and fertilizing, the soil around the roots of the plant is compacted, and a thin crust appears on the surface of the earth, which prevents the flow of oxygen. To prevent this from happening, be sure to carefully loosen the surface of the ground - for this it is better to use a pick stick so as not to damage the roots.

It is important to harden the plants. Approximately 20-25 days before planting, you need to start hardening the seedlings, accustoming the plants to direct sunlight. You can take the container with tomatoes to the balcony or put it outside. At the same time, you should start hardening tomatoes gradually: first expose the seedlings for several hours, then increase the time, the main thing is to remove the plants in a warm place at night... In just a couple of days, you can expose the seedlings for a full day and night. Now you know why tomato seedlings turn yellow, which means you can quickly fix the problem if it appears.

Hello dear readers!Today you will not surprise anyone with the fact that you can buy everything that comes into your head at every step, therefore, the sale of tomato seedlings has not amazed anyone for a long time either. Any variety to choose from and now - a box of young plants is yours, without painful months of nursing on the half-dark windowsill of the Khrushchev.

Growing seedlings at home is not easy, and many do buy ready-to-plant plants at the risk of getting sick, weak or unsuitable for growing in the conditions prepared for them. But that's if you are a beginner.

An experienced gardener for plants will immediately understand both the involvement in the variety and the state of health, but that is why he is experienced, so as not to do this, but to grow it himself. If you have no time to bother with growing, and you still go to the market, then read,.

A tomato at the beginning of its growth can be quite picky, and in any case, whether you bought seedlings or grew it yourself, it can surprise you in the form of yellowed leaves. The only difference will be that you studied your shoots during their growth, and in what conditions they grew purchased ones - a mystery.

One way or another, it will still be necessary to identify the cause to eliminate the symptom that has arisen, which clearly signals the poor health of the tomatoes. In this article, we will consider possible options for our actions if the leaves of tomato or pepper seedlings turn yellow.

Leaf yellowing is a fairly common nuisance that can happen to tomato seedlings, even if they receive both nutrition and light. There can be many reasons for this phenomenon:

• You overdid it and flooded the plants with the next watering
• You overlooked and undernourished the plants - now they are hungry
• You are growing seedlings in tight containers that are already filled with roots.
• Your plants are nitrogen deficient and have no room for further growth

• Your plants are deficient in light, which means they are starving again.
• Your plants are suffering from acidic soil, check if the soil in the box is white
• Your plants are frozen, sick and will soon shed yellowed leaves

Waterlogging

Excess moisture in the soil can provoke a fungus that develops in dampness, or rotting of the roots, or both at the same time. Plus, the water washes out all the nutrients, and the plant is starving. Here are the yellow leaves.

There is no need to wait for moisture to evaporate from the soil, you just need to change the substrate of the plant - there is no other way out. And don't forget to make a drain and a drain hole in the new container.

In order to determine the optimum moisture content in the soil for seedlings, you need to stick your finger in the ground. If the soil is moist and sticks to the skin, then watering should be postponed.

Phytophthora

You should take care of preventive measures to combat late blight in advance, even at the seed stage. For this, the seeds must always be pickled in a solution.

When the fungus nevertheless reached the seedlings and settled on the stem and leaves, you will have to change the substrate and disinfect the boxes or glasses, and destroy the infected shoots. Only such extreme measures will save the remaining plants from death.

Nutritional deficiency

It is recommended to feed seedlings only if it requires it. Usually tomatoes are sown in nutrient soil, where all the necessary elements are already present, and after a certain time, when they run out, young tomatoes are fed with special micronutrient fertilizer for seedlings. Maybe the moment of feeding has just come, if the lower leaves have turned yellow, and there are no other reasons for this.

Lack of light

With a lack of light, the seedlings first stretch out and become thinner, and then begin to turn yellow. Direct sunlight can be detrimental to young shoots, but the lack of light will be detrimental to them. Seedlings need to be accustomed to the sun gradually, bringing plants into the light for a certain time, gradually increasing it.

Try not to thicken the planting and not be greedy. It is better to grow 20 sturdy tomatoes than 50 thin blades of grass that cannot withstand transplants.

Nitrogen deficiency

With a nitrogen deficiency, the leaf plate itself turns yellow, but the veins remain green, so this symptom is easier to track down than others. Nitrogen is responsible for plant growth and is very necessary for tomatoes at the beginning of development.

With its lack, the plant first turns pale and becomes light green, and if measures have not been taken, it begins to signal starvation with yellow leaves. But even at this stage, fertilizing with nitrogen fertilizer will save your tomatoes.

Restricting root growth

If you have not calculated the volume of the cups and underestimated your plants, it may happen that they have outgrown their containers and filled the entire soil with their roots. Transplanting tomatoes into a larger container will help them come to their senses.

But give them time for this, it often happens that the leaves of the seedlings turn yellow after transplanting and experience temporary stress in larger containers. Often, tomato seeds are immediately sown in separate cups and do not waste time picking, which takes away strength from the seedlings.

Soil acidification

The acidic soil takes away the last strength from tomatoes, and makes them defenseless against the threat of infection.

Place the glass on a black bag and sprinkle some soil from the seed box on top. Place a drop of 9% vinegar on top. The absence of any reaction will indicate that the soil is acidic, and this has a detrimental effect on the seedlings (read how easy and simple it is).

Application to the soil will help neutralize acidification.

Lowering the temperature

A sudden cold snap can overtake even on the windowsill of a closed window,

therefore, you should always follow the weather forecast and wrap up the shoots. This problem is especially acute when the seedlings are grown in a greenhouse or greenhouse. It is necessary to provide plants with a reliable shelter that does not obstruct sunlight, especially during flowering.

So, let's summarize. If you originally planted the pickled seeds in separate cups, having previously placed nutrient soil in the container and provided them with a drainage system, then you just have to monitor the lighting and water the plants with warm water in time. That's all the secrets of growing seedlings without yellowing foliage.

Good harvest and see you soon!

Sincerely, Andrey!

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The key component of any plant is chlorophyll. Thanks to it, a vital connection between the sun and the biosphere is realized: the chlorophyll contained in plant cells, under the influence of sunlight, synthesizes organic substances from water and carbon dioxide. Yellowing of plants indicates a violation of the formation of chlorophyll in them - a disease called chlorosis. So the answer to the question of why tomato seedlings turn yellow is quite simple. But this alone is not enough - you need to get to the reasons. And there are several of them.

The most common of these is a violation of the nutrition of the root system. This happens due to its damage, physical or temperature (hypothermia). But if the temperature regime is violated, chlorosis affects the entire plant. And if, say, the planting on the garden led to mechanical damage to the root system, only the lower leaves turn yellow. In this case, you should wait for the rooting of the seedlings and the appearance of new adventitious roots - the tomato will cope with chlorosis on its own.

To determine the cause of chlorosis, it is enough to look closely at the leaves of a young plant. And if it turns yellow from the older (lower) leaves, one should also suspect the lack of one of the chemical elements important for the tomato.

Most often, chlorosis of tomato seedlings indicates a nitrogen deficiency. The leaf veins of a bluish-red color and small leaves on the entire plant as a whole speak about it. The lower leaves die off after yellowing. If the seedlings are grown for sale, you don't even have to try to bring them to the market: clear signs of chlorosis will scare off buyers from it, and no explanation of why tomato seedlings turn yellow will help.

Yellowing can also cause potassium deficiency, but here the process often goes too far due to the accumulation of ammonia nitrogen, accompanied by dehydration of the leaves and their twisting, up to the appearance of signs of tissue necrosis.

The next reason why tomato seedlings turn yellow is zinc deficiency. He also gives himself away with numerous small specks of yellow color on young leaves. They are also abnormally small, may be entirely yellow, sometimes curling upward. in contrast, it appears immediately over the entire surface of the sheet, but passes much faster.

If chlorosis of young leaves of seedlings begins from their base, and the color from yellow-green through lemon-yellow becomes yellow-white, then the plant reacts to iron deficiency. It is reflected only on young leaves, without passing on to older ones. This type of deficiency can occur at an early stage of growing seedlings, if its round-the-clock illumination is not supported by fertilizing with iron content. As soon as they are renewed, the plant returns to its normal state in just a few hours.

But micronutrient and nutrient deficiencies are relatively easy to fix. It is a completely different matter when the answer to the question of why tomato seedlings turn yellow is as follows: this is fusarium. This dangerous fungal disease can affect tomatoes at any age. It is also difficult to deal with it because the ailment may be revealed too late. The most effective remedy is prevention. But if the seedlings are already affected, it is necessary to immediately isolate healthy plants from diseased ones; treat the first with the drug, the second - immediately destroy (burn).