People who love the earth know how important it is to monitor the condition of the soil. Therefore, they apply fertilizers and take care of the land as much as possible. But investing in agricultural practices will not prevent plant problems.
Many questions immediately arise about why the seedlings turn yellow or develop poorly, and the leaves fall from the seedling several weeks after transplantation. Such cases occur regardless of the type of crop, planting time, or age of the plant. There are many reasons for this. The problem can be solved if the root cause is eliminated.
Reason No. 1 - defective seedling seeds
The sprouts hatch from the seed coat, which provides minerals in the first days of growth. But if the seeds were taken from infected vegetables, the effect will be the opposite.
Therefore, on the eve of landing it is necessary:
- Choose disease-resistant hybrids that are marked “F1”;
- Calibrate the seed, selecting the largest and healthiest seeds;
- Harden the seeds in cool water (plus 12-16 degrees Celsius) for 4-6 hours;
- Treat the seeds in a 2% solution of potassium permanganate.
By observing the listed requirements, the risk of seedlings turning yellow in the first 20 days from germination is significantly reduced. Even at one month of age, seedlings grown from healthy seeds rarely turn yellow and wither.
Reason No. 2 - lack of light
Since seedlings are grown indoors from February to May, their sprouts are by default poorly lit. A lack of light often contributes to the yellowing of sprouts when they are no more than 5 days old and they are covered with glass or film.
In fact, seedlings need:
- Additionally, illuminate with phytolamps so that daylight hours last at least 14 hours a day;
- Grow next to windows that face south, east or southeast;
- Keep it open so that the sun's rays fall on the above-ground part of the sprouts.
You need to understand that vegetable crops bear fruit at different times. Therefore, early cucumbers should be planted in April-May, peppers - in March-April, tomatoes - from February to May inclusive.
The corresponding schedule allows you to prevent a shortage of light due to the fact that closer to summer the daylight hours increase.
What to do if the leaves turn yellow
All reasons that can cause yellowing leaves weaken the seedlings and increase their vulnerability to other adverse factors, so act quickly.
But we should not forget about the principle - unscheduled fertilizing and pest control should be carried out to the exclusion of other causes.
For example, you should not give nitrogen “just in case”; its excess leads to a delay in flowering.
Lighting
If a plant shows symptoms of light deficiency, it is necessary to provide it with 14-16 hours of daylight using a phytolamp. A bicolor model with blue and red spectrum lamps is suitable for seedlings. This combination stimulates photosynthesis processes.
Even if the leaves do not turn yellow, the consequence of pulling the seedlings can be a loss of 30% of the harvest. The internodes of such plants are located at a greater distance from each other than usual, so the bush will have fewer fruit clusters.
To restore overgrown peppers, you should water them with Atlet growth stimulator and reduce the room temperature to +20...+23°C.
The product helps the stem grow in thickness and leaves, and also causes a redistribution of nutrients - the plant devotes all its energy to growing roots.
For watering, prepare a solution of 150 ml of the drug and 1 liter of water, pour 30-50 ml under the bush. Do not water for 2-3 days.
If the seedlings have become very elongated, it is worth spraying the bushes with the same preparation so that it works faster.
The concentration is the same, spray until the drops drip from the leaves. After treatment, do not water for one day. The drug cannot be used if there are less than 3-5 days left before planting in the ground.
Overheating
Seedlings that have received heat stroke need to be shaded and watered. It is recommended to spray with a solution of the Zircon preparation at a concentration of 1 ml per 10 liters of water.
It is advisable to boil and cool the water or add 2 teaspoons of boric acid or vinegar to it, since most often it is alkaline and the product will not work in it.
Shield seedlings from direct sunlight every day. The greenhouse should be ventilated; in a glass greenhouse, the roof should be whitened with a chalk solution or covered with a light-colored cloth. Gradually the plants will return to normal.
Hypothermia
In addition to restoring normal temperature conditions, it is worth supporting the pepper’s immunity.
For this purpose, it is best to spray the bush with Epin-extra (2 ml per 10 l). Prepare the water in the same way as for Zircon.
If the plants have been frozen, repeat the procedure after 7-10 days. Do not store the prepared solution for longer than a day.
Excessive watering
Stop irrigation and spray with a solution of 1 ml of Zircon, 1 ml of Cytovit and 10 liters of water. If this does not help, replant the bush.
It is difficult to save seedlings that have been affected by blackleg; it is more advisable to burn the diseased plant and take care of the rest. They should be transplanted into different soil, provided with light and watered moderately.
Make the first watering with “Fitoforin-M” - 30 g of powder per 10 liters of water. Give 150-200 ml per bush.
The product acts against fungi due to the bacteria Bacillus subtilis, so it is important to prepare the solution 1-2 hours before watering and should not be kept in the light, otherwise the microorganism will die.
Lack of water
Plants that were slightly damaged will recover when watering is resumed, and spraying with the Epin-Extra stimulant (2 ml per bucket) will increase the chances of recovery.
If the bush has already laid down, it is advised to immerse the pot in a bowl of water at room temperature for a few minutes so that the earthen lump is completely wet, and then put a plastic bag over the container.
The pepper should spend at least 24 hours in such an individual greenhouse.
Heavy ground
It is best to transplant the seedlings into another substrate. Good loose soil for this crop can be made from peat, humus and sand, taking them in a ratio of 2:2:1.
If replanting is not possible, it is necessary to loosen the soil after each watering.
Dense planting
Young seedlings can be thinned out - pull out the excess ones, leaving 2 cm of distance between the sprouts. Older plants should be planted in different containers.
Carry out the procedure very carefully - intertwined roots are almost impossible to untangle without damage. The easiest way to do this will be in water.
Before planting, it is useful to soak the roots in a heteroauxin solution for 18-20 hours.
Dissolve 1 tablet (0.1 g) in 5 liters of water. You can replace this drug with Kornevin. For 5 liters of water you will need 5 g of powder, soak for about 6-10 hours.
In both cases, after planting, you can water the peppers with the used solution, 50-60 ml for each bush.
For the next couple of days, keep the plants in the shade and water in small portions, not allowing the soil to dry out.
After transplantation or root damage
If the seedlings do not take root in a new place, it is necessary to stimulate the root formation processes.
To do this, you can water the bush with 50 ml of a solution of “Kornevin” (10 g/10 l), “Kornerosta-M” (10 g/10 l) or spray it with “Zircon” (1 ml/10 l).
Nutritional deficiency
Nitrogen deficiency can be replenished by fertilizing with complex preparations (Fertika Lux, Ferovit, Izumrud, etc.) intended for irrigation.
But foliar feeding will work faster. For spraying, you can prepare a 0.15% solution of carbamide (urea).
Microelements are applied only by foliar method:
- magnesium – magnesium sulfate (15 g of substance per 10 liters of water);
- sulfur – ammonium sulfate (10 g per 10 l);
- iron - iron sulfate (25 g per bucket).
Reason No. 3 - waterlogging of soil and air
If in summer adult vegetable plants turn yellow due to the heat, then in winter and spring the problem arises due to waterlogging of the soil and air. Frequent watering and spraying oxidize the soil, after which it is difficult for the plant to develop.
The stems quickly turn pale and the leaves turn yellow. In this case you will have to:
- Avoid spraying completely;
- Reduce the number of waterings to once a week;
- Provide the seedlings with good ventilation (the temperature should be at least plus 20 degrees Celsius);
- Improve lighting;
- Sprinkle some ash on the soil.
Usually within a week the seedlings become green. If this does not happen, other detrimental conditions contribute to yellowing.
Seedlings turn red or blue
Red, blue, or reddish-purple tinges on the undersides of seedling leaves or stems may indicate a serious deficiency of nitrogen, potassium, or phosphorus in the soil. At first, parts of the plant usually turn pale (yellow), and then turn into such unusual colors, which is often accompanied by growth retardation. This can be especially pronounced in cold rainy weather, when small roots do not have time to fully absorb useful elements. The solution is timely feeding.
- Nitrogen, phosphorus, potassium - signs of deficiency and excess in plants
What do excess or deficiency of nitrogen, phosphorus and potassium lead to? Find out in our infographic!
Also, the stems of seedlings may begin to darken (turn blue) due to temperature stress - for example, when the air in the greenhouse and the upper centimeters of the soil under the shelter have already warmed up slightly, but in the depths the soil is still cold. If the temperature does not level out, young plants may noticeably weaken.
Reason #4 - lack of moisture
A high-quality substrate retains moisture for a week. But as the root system and the seedlings themselves grow, the peat quickly loses beneficial elements and bacteria. Therefore, 30-50-day seedlings have to:
- Water every 3-4 days, spending 0.5 liters for each bush;
- Feed with solutions of various fertilizers;
- Replant into a new substrate.
In this case, air humidity should not exceed 60 percent. To comply with this requirement, it is enough to refuse spraying. As for watering, they are carried out before noon (in the morning hours the plant best absorbs moisture and nutrients).
Most common reasons
Why do the lower leaves of tomatoes dry out, the seedlings do not grow, wither and what to do in this case?
Priming
The abundance of peat in the prepared substrate for sowing seeds can slow down the growth of seedlings and form light yellow shades on the foliage. Also, the substrate must contain sand and perlite , otherwise after watering the soil will turn into a heavy lump, which will interfere with the normal development of roots.
Important. Soil salinity is one of the main reasons for yellowing of the leaves of tomato seedlings.
An excess of salt can be detected by white and yellow spots on the surface of the earth. Salting occurs from hard water or excess fertilizer.
To solve the problem with the soil, you will have to replant the seedlings, having previously created the optimal soil mixture, it consists of:
- Washed river sand – 1 part.
- Sod land -2 parts.
- Leaf soil or peat - 1 part.
- Perlite – 1 part.
- Coconut substrate – 1 part.
- Wood ash – 0.5 parts.
Salinization of the soil can be treated by removing soil from the surface (3 centimeters will be enough) and watering with soft rainwater.
Watering
Tomato seedlings need a special watering regime. The basic requirements are:
- Infrequent but abundant watering.
- Warm water.
- The optimal time of day for the procedure is morning or evening.
- Water pours under the root, avoiding contact with the leaves.
An excess of liquid and its deficiency are equally harmful to seedlings . Stagnant moisture deprives the roots of oxygen, resulting in yellowness on the leaves, the roots rot, and the fruit tastes watery. Lack of moisture can be recognized by the lower leaves of the seedling being curled and yellow, while the top remains green, due to the fact that the plant is devoting resources to the development of new leaves.
Advice. To solve the problem, it is necessary to normalize the flow of water by loosening the soil and watering abundantly, provided that it has dried sufficiently after the previous watering.
Nutrition
Microelements are a very important factor affecting the health of the plant and seedlings as a whole. Based on certain signs, you can determine what exactly the seedlings lack and supply it with it.
- Potassium . Its deficiency is expressed in yellowing of the edges and tips of leaves, when the veins remain green. To replenish, you can feed the seedlings with potassium sulfate or potassium humate.
- Nitrogen . Its deficiency is visible by yellowed tips and veins. Yellowness appears on the lower leaves of the seedlings, and the upper ones decrease in size. Treatment is urea, ammonium nitrate, rotted mullein or chicken droppings.
- Calcium . Its absence curls and deforms the leaves. The upper leaves turn yellow, but the lower ones remain green. The situation can be corrected with calcium nitrate.
- Zinc . Its lack makes the plates of the lower sheets pale yellow, as if colorless. The solution is to spray the leaves of the seedlings with zinc sulfate.
- Iron . Its deficit is to reduce the size of new sheets. The foliage at the top turns yellow, with dark green protruding veins. You can compensate for the deficiency by adding iron chelate to the watering liquid or by spraying the leaves with vitriol.
- Magnesium . Its deficiency makes the edging along the contour yellow, and leaves the veins green. Adding magnesium sulfate to the liquid helps.
- Phosphorus . Its deficiency makes the stem and leaves purple, and the top of the seedlings turns yellow. Problems are solved by extracting superphosphate.
- Manganese . Its deficiency turns the leaves yellow and dries them out, causing them to wilt and fall off. To normalize the situation, it is enough to spray the foliage with zinc sulfate.
If several elements are missing, when the foliage of the seedlings becomes yellow-green and the stem becomes thin and elongated, you can use a complex fertilizer. In order to improve the digestibility of fertilizing and prevent burns, the procedure for applying fertilizer should be carried out on a moist substrate .
Lighting
Tomato seedlings love light and react negatively to prolonged, cloudy weather, even turning yellow.
To ensure that the seedlings receive a sufficient dose of lighting, at home it is recommended to place the seedlings on a windowsill located on the sunny side.
In addition, you can get special phytolamps that will help extend daylight hours. Plants should be exposed to light for approximately 12 hours .
Too much light is also harmful, as the plant can burn. In addition, it is at night that seedlings absorb useful substances, and therefore artificial lighting is not needed at this time.
Close fit
Tomato seedlings do not like cramped conditions . In the absence of space, the roots become ill and the seedlings begin to wither, which is reflected in the yellowed foliage.
Important . Optimal density of planting material: between rows of tomatoes - at least 5 cm, and between seedlings - 2 cm.
Diseases
Diseases can lead to yellowing of the leaves of seedlings, as well as to the death of the crop. The most common of them are:
- Fusarium . The disease can be identified by the wilting of the lower leaves and the yellowness of all other leaves and the top of the seedling. If the plant is not completely affected by yellowness, you can try to save it by replanting it in clean soil. If the plant is completely spoiled, all that remains is to throw it away to avoid further spread of the infection. Spraying with phytospirin also helps.
- Black leg . An infectious disease that is very dangerous for many plants, including tomatoes. Its presence is visible by rotting of the root collar, yellowing and falling of leaves. The plant as a whole becomes lethargic and falls. There is no cure for blackleg; the main thing is to destroy infected seedlings before the bacteria are transferred to healthy ones.
- Rot . Excessive humidity and lack of heat lead to rot. It can be diagnosed by yellowing, falling and rotting of plants. Sick seedlings should be uprooted and thrown away, and healthy ones should be replanted.
Reason #5 - soil contamination
Sometimes farmers refuse to purchase ready-made substrate and use clean water for growing seedlings. This raises the risk of plant contamination from the soil. If the sprouts turn yellow, it is necessary to inspect the top layer of the substrate.
If it is covered with a crust or fungal coating, then a set of measures must be immediately carried out with the seedlings:
- Calibration of diseased plants;
- Transplantation into a new substrate;
- Watering with a solution of “Fitosporin-M”, “Alirin-B”, “Trichodermin” or “Gamair”.
In order for the seedlings to take root better, it is recommended to alternate the biofungicide solution with the Kornevin or Epin-Extra solution. These stimulants accelerate the development of the root system and strengthen the crop's immune system. After a week, the seedlings are fertilized with a nutrient solution through watering.
Yellow leaves on seedlings are the result of poor care
And, finally, the simplest reason for yellowing leaves is failures in care. The leaves of the seedlings will definitely turn yellow if:
- plants stand on the windowsill in bright direct sunlight,
- the indoor air is dry,
- the seedlings stand in a constant draft,
- the seedlings are flooded, the drainage is poor, the water stagnates and the roots simply rot,
- the soil is oversaturated (and this is bad, as well as a lack of nutrients),
- seedlings are watered with hard water, as a result a white coating appears on the surface, which impedes metabolism.
If you want to destroy seedlings, follow these simple rules
