There are several reasons why tomato seedlings turn yellow. It is imperative to deal with the problem in a timely manner. A good harvest can only be obtained when the seedlings are strong and healthy. Therefore, you need to know how to care for it.
Lack or excess of microelements
If you understand the situation and determine the true problem of yellowing and drying of seedling leaves, then dealing with the problem will become much easier. Seedlings grown on a windowsill require fertilizing for full development. But not only a lack of any substances leads to a problem, but also their excess.Therefore, you must follow the instructions for dilution and dosage.
The following are the main unfavorable factors why the leaves of tomato seedlings turn yellow.
- If the lower leaves of tomato seedlings turn yellow and the veins turn red, this often occurs as a result of a lack of nitrogen. The leaves are small and light green in color. Fertilizing with nitrogen will help correct the situation.
- The lower leaves of 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 out and turn yellow, you need to rule out potassium deficiency.
- A lack of zinc leads to yellowing of the edges of the leaves, their curling and the appearance of dark spots.
- When the yellowed areas begin to lighten, you need to add nutritional components with iron.
- If the top leaves turn yellow first, this indicates a lack of phosphorus. An excess of this component is indicated by the complete yellowing of all leaves on the plant.
- If there is little manganese in the soil, the leaves initially become covered with yellow spots and then dry out completely.
What to do if tomato seedlings turn yellow? If the seedlings do not grow well and other problems appear, it is necessary to provide them with the necessary fertilizers in a timely manner. This will prevent the greens from yellowing, drying out and curling. It is recommended to apply fertilizer to each bush separately.
Common causes of the problem
There are many reasons why the leaves of tomato seedlings may turn yellow, but the most basic ones that gardeners encounter are the following.
- It is recommended to plant seeds only in special soil. Ordinary soil from the garden or bought in a store, but intended for flowers, will not work.The problem of why the leaves of tomato seedlings turn yellow may be associated with acidic, dense soil. There may be a lot of fertilizer added to the soil.
- Leaves may turn yellow due to damage to root branches during picking or sudden changes in air temperature, as a result of which the nutrition of the plant is disrupted.
- Why else could problems arise? Lack of soil or cramped container where the seedlings are planted. When sowing seeds, distance between holes should be maintained. If you plant seeds close, the sprouts begin to stretch, trying to absorb light. Dense plantings have few nutrients and the roots are intertwined.
- Seedlings may not have enough light, which leads to thinning and elongation of the stem. Tomatoes need plenty of daylight every day. Seedlings must receive light for about 12 hours a day, otherwise development stops. Often there is insufficient lighting on the windowsill, so you need to illuminate it with a lamp.
- Why do tomato seedlings dry out? The answer may be related to the dry, hot air in the room. It causes the leaves to dry out and change color.
- If seedlings are grown in a cool place, then the nutrients are not absorbed, the development of sprouts slows down and the appearance changes.
- Among the common causes are errors related to watering.
What to do when tomato seedlings turn yellow and wither? If fertilizing is applied correctly, then you need to ensure that watering is organized correctly. Watering should be moderate and even. If you water too often and excessively, the soil will begin to turn sour, and oxygen will be poorly supplied to the roots. In this case, the lower and cotyledon leaves of the seedlings begin to turn yellow.
On the contrary, lack of moisture causes tomato leaves to dry out. Dry soil prevents the penetration of nutrients into the plant. Dry soil can be easily corrected; it is enough to water the sprouts with settled water in a timely manner.
If the soil is watered with hard water, a crust with a white or yellowish coating forms on the surface. The roots begin to pull all the microelements from the plant into the soil. Water for irrigation should be warm and settled.
You need to water in the morning or evening, avoiding moisture getting on the green part of the plant. If you water at lunchtime, when the sun is shining brightly, the plant may get burned.
Why did the tomato seedlings start to feel bad? Other reasons why tomato seedlings have turned yellow include infectious diseases (blackleg, fusarium, septoria), the use of low-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 out, what to do in such a situation? The problem can be provoked by temperature fluctuations, watering with cold water or carrying out a picking procedure. In these cases, literally within a day, the tips of the leaves begin to change color and shape.
Tomato seedlings turn yellow after picking as a result of exposure to stress. The picking must be carried out according to all the rules, otherwise the root branches may completely die off and the young shoots will no longer be able to be saved.
Picking rules to avoid problems:
- the individual containers into which the plant is supposed to be planted must be washed well and the soil disinfected;
- you need to start the procedure when the seedlings have 2-3 leaves;
- at the bottom of the container you need to make holes to drain excess liquid and provide drainage;
- It is recommended to pinch the main root a little, which will make the root system more branched and stronger.
If these rules are not followed, the tips of the leaves of tomato bushes dry out, the veins turn yellow, the stem weakens and withers.
If the roots are not severely damaged, then you can use drugs such as Zircon, Epin. They promote root formation and increase immunity, which is so important after picking.
Preventive actions
In order for tomato seedlings to feel comfortable on the windowsill, you need to create conditions. It is necessary to choose the right soil, provide sufficient lighting, normal temperature and humidity. Do not forget about watering and timely application of fertilizers.
What can be done if the tomato seedlings have turned yellow due to overwatering of the soil? If the leaves just turn yellow, but no white coating has formed, you can sprinkle dry wood ash on top and, of course, reduce the frequency of watering.
Transplantation of seedlings should be carried out urgently in the following cases:
- excess moisture led to acidification of the soil;
- excessive alkaline environment;
- watering with hard water;
- excess fertilizer;
- cramped container or little soil.
Individual sprouts are transplanted into prepared new containers with special moistened soil. Before planting young sprouts 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 fertilizing will help prevent tomato seedlings from turning yellow. If there is a deficiency of any element, the plant’s immunity decreases. The 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. Repeated feeding is carried out after another 14 days. Both mineral and organic components are suitable, which you can mix yourself or buy ready-made in the store.
Before applying fertilizer, lightly moisten the soil. Moisturizing will avoid burns to the root system and will promote better absorption of nutritional components.
Why do the leaves of tomato seedlings dry out and their color change? The leaves of tomato seedlings dry out and change color due to lack of oxygen. After several regular waterings and fertilization, the top layer of soil becomes 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 too 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. This way, the plants will get used to direct sunlight and fresh air. It needs to be hardened gradually. First, you need to take the container with seedlings out onto the balcony with an open window for a couple of hours.Every day, the time the seedlings spend in the fresh air should be increased, but at night they must be removed to a warm place.
