Reasons why tomato seedlings may turn yellow and what to do
There are several reasons why tomato seedlings turn yellow. It is imperative to deal with the problem in time. A good harvest can only be obtained when the seedlings are strong and healthy. Therefore, you need to know how to take care of her.
Lack or excess of micronutrients
If you understand the situation and determine the true problem of yellowing, drying of the leaves of seedlings, then it will become much easier to deal with the problem. Seedlings grown on the windowsill require top dressing for full development. But not only the lack of any substances leads to a problem, but also their excess. Therefore, you must follow the instructions for dilution and dosage.
The following main unfavorable factors are distinguished, why the leaves of tomato seedlings turn yellow.
- If the lower leaves of tomato seedlings turn yellow, and the veins acquire a red tint, this often happens as a result of a lack of nitrogen. The leaves are small and light green in color. Top dressing with nitrogen content will help to correct the situation.
- The lower leaves of the seedlings on the windowsill turn yellow due to sulfur deficiency, and they become hard and dense to the touch.
- When the tips of the leaves dry and turn yellow, potassium deficiency must be ruled out.
- Lack of zinc leads to yellowness at the edges of the leaves, their curling and the appearance of dark spots.
- When the yellowed areas begin to lighten, then you need to add nutrients with iron.
- If the upper leaves turned yellow first, this indicates a lack of phosphorus. The excess of this component is indicated by the complete yellowing of all leaves on the plant.
- If there is little manganese in the soil, then initially the leaves are covered with yellow spots, and then completely dry out.
What to do if tomato seedlings turn yellow? In the case when the seedlings grow poorly and other problems appear, it is necessary to provide them with the necessary fertilizers in a timely manner. This will help prevent yellowing, drying and curling of the greenery. It is recommended to apply fertilizers separately for each bush.
Common causes of the problem
There are many reasons why the leaves of tomato seedlings can turn yellow, but the most basic ones that gardeners face are the following.
- It is recommended to plant seeds only in special soil. Ordinary land from the garden or store bought but intended for flowers will not work. The problem of why the leaves turn yellow in tomato seedlings may be due to the acidic, dense soil. A lot of fertilizer may have been applied to the soil.
- Leaves can turn yellow due to damage to the root branches during a pick or a sharp change in air temperature, as a result of which the plant nutrition is disrupted.
- Why else can problems arise? Lack of soil or a tight container where the seedlings are planted. When sowing seeds, keep the distance between the holes. If you plant the seeds close, the sprouts begin to stretch out, trying to absorb light. Dense plantations have few nutrients, the roots are intertwined.
- The seedlings may lack light, resulting in a thinning and stretching stem. Tomatoes need plenty of daylight every day. The seedlings should receive light about 12 hours a day, otherwise development will stop. Often the lighting on the windowsill is insufficient, so you need to illuminate with a lamp.
- Why tomato seedlings dry out, the answer may be associated with dry, hot air in the room. It becomes the culprit that the leaves dry out and change color.
- If the seedlings are grown in a cool place, then the nutrients are not absorbed, the development of the sprouts slows down and the appearance changes.
- Watering errors are a common cause.
What to do when tomato seedlings turn yellow and wither? If fertilizing is applied correctly, then you need to see if watering is organized correctly. Watering should be moderate and even. If you water it too often and too much, the soil will turn sour and oxygen will not flow well to the roots. In this case, the lower and cotyledon leaves of the seedlings begin to turn yellow.
On the contrary, a lack of moisture causes the leaves of tomatoes to dry out. Dry soil prevents the penetration of nutrients into the plant. The dryness of the soil is easy to correct, it is enough to water the sprouts with settled water in time.
If the soil is watered with hard water, a crust with a white or yellowish coating forms on the surface. The roots begin to draw out all trace elements from the plant into the soil. Water for irrigation should be warm and settled.
Watering should be done in the morning or evening, avoiding moisture on the green part of the plant. Watering at lunchtime when the sun is shining brightly can burn the plant.
Why did tomato seedlings feel bad? Other reasons for which tomato seedlings have turned yellow include infectious diseases (black leg, fusarium, septoria), the use of poor-quality fertilizer or improper dilution. For example, if gray spots appear simultaneously with yellowing of the leaves, then this may be a disease such as septoria. The pathogen enters the plant from the soil.
Drastic changes
Sometimes it happens that suddenly tomato seedlings turn yellow and dry, what to do in such a situation? Temperature fluctuations, watering with cold water or carrying out a picking procedure can provoke a problem. In these cases, literally in a day, the tips of the leaves begin to change color and shape.
Tomato seedlings turn yellow after picking as a result of stress. The pick must be carried out according to all the rules, otherwise the complete dying off of the root branches may occur and the young shoots cannot be saved.
Pick rules to avoid problems:
- individual containers in which the plant is supposed to dive must be washed well, and the soil must be disinfected;
- you need to start the procedure when the seedlings are expanded by 2-3 leaves;
- holes must be made at the bottom of the container for excess liquid to escape and drainage must be provided;
- it is recommended to pinch the main root a little, which will make the root system more branched and strong.
If these rules are not followed, the tips of the leaves dry out in tomato bushes, the veins turn yellow, the stem weakens and withers.
If the roots are not badly damaged, then you can use drugs such as Zircon, Epin. They contribute to root formation and increase immunity, which is so important after a pick.
Preventive actions
In order for tomato seedlings on the windowsill to feel comfortable, you need to create conditions. It is necessary to choose the right soil, provide adequate lighting, normal temperature and humidity. Do not forget about watering and timely fertilization.
What can be done if tomato seedlings turn yellow due to overflowing soil? If the leaves just turned yellow, but no white bloom was formed, you can sprinkle it on top with dry wood ash and, of course, reduce the frequency of watering.
Transplanting seedlings should be carried out urgently in the following cases:
- excessive moisture led to acidification of the soil;
- excessive alkaline environment;
- watering with hard water;
- excess fertilizer;
- tight capacity or little soil.
Individual shoots are transplanted into prepared new containers with special moistened soil. Before planting young shoots in a container, you need to examine the roots and remove rotten and weak root branches.
After planting, it is recommended to water the plants with water with a few drops of potassium permanganate and move them to a shaded room for a couple of days. As soon as the stem straightens, and the yellowed foliage begins to turn green, the seedlings are transferred to the windowsill.
If the leaves of tomato seedlings turn yellow, what can you do? Timely application of top dressing will help prevent tomato seedlings from turning yellow. With a deficiency of some element, the plant's immunity decreases. Seedlings become susceptible to diseases, which leads to their death.
The first feeding is carried out with the emergence of seedlings, this is approximately 8 days after sowing the seeds. Re-feeding is carried out after another 14 days. Both mineral and organic ingredients are suitable, which you can mix yourself, or buy ready-made in the store.
Before fertilizing, the soil should be slightly moistened. Moisturizing will help to avoid root burns and promote better absorption of nutrients.
Why do the leaves of tomato seedlings dry and their color changes? In tomato seedlings, the leaves dry out, and the color changes, due to a lack of oxygen. After several successive watering and fertilization, the topsoil is compacted and a crust forms, which impairs air circulation. The problem can be solved by loosening the soil. After each watering, you need to loosen the soil without going deep, so as not to damage the root system. You can use a pick stick.
23 days before transplanting seedlings into open or closed ground, it is necessary to harden them. Thus, the plants will get used to direct sunlight and fresh air. You need to harden gradually. First, you need to take the container with seedlings to the balcony with an open window for a couple of hours. Every day, the time the seedlings stay in the fresh air should be increased, but at night they must be removed to a warm place.
