Surely every gardener at least once tried to grow tomato seedlings on his own. But unfortunately, not everyone and not always succeeds, because even seemingly healthy, grown seedlings can begin to “mope”. So, the most common problem is that the leaves of tomato seedlings fall off. There may be several reasons for such trouble. Often they are associated with malnutrition, watering of plants, the development of certain diseases or the presence of inappropriate microclimatic conditions. To solve the problem, you should analyze the situation and determine the cause, choosing a way to eliminate it.
Watering
The most banal reason why tomato seedlings can turn yellow and fall off is a lack of moisture. Seedlings should be watered moderately and regularly. At the initial stage, tomatoes should be watered once every 1-5 days. After the appearance of true leaves, this should be done more often: 6 time in 1 days. Plants with 4-5 true leaves should be watered every 6-2 days. Such a schedule for watering tomato seedlings is recommended. It should be followed, however, in sunny weather in conditions of low humidity, the soil can dry out quite quickly and extraordinary watering or spraying can be used to prevent drying out.
It is worth noting that not only prolonged drought can lead to leaf fall, but also excessive watering of young tomatoes. Being constantly in water, the roots of plants receive less oxygen and begin to rot. A symptom of such decay is the fall of tomato leaves. Given such conflicting facts, it should be noted once again that watering tomato seedlings should be regular and moderately plentiful.
Lighting
Another very important condition for the normal growth of seedlings is adequate lighting. So, daylight hours for tomato seedlings should last 8-10 hours. With a lack of lighting, the leaves of tomatoes become long, thin. Their color is pale green. The consequence of such a lack of lighting can be the fall of the lower leaves of seedlings, which are maximally shaded by young shoots. You can fix the problem by artificially illuminating plants with fluorescent lamps.
Temperature
Tomatoes are heat-loving plants that arrived in our latitudes from the tropics. However, high temperatures can severely damage young seedlings. So, the temperature is over +300C is able to burn tomatoes. With such a lesion, the tomatoes turn yellow and shed their leaves. Of course, in the spring in apartment conditions such temperature records are rare, but if necessary, spraying with a solution of urea will help save tomato seedlings from the heat. To prepare it, dissolve 1 tablespoon of the substance in a bucket of water.
Low temperatures can harm tomatoes no less than heat. At temperatures below +100Since the root system of tomatoes shrinks, it stops absorbing nutrients from the soil. As a result of such hypothermia, tomato leaves acquire a bluish tint, the seedlings wither and eventually shed their leaves.
Food
It’s no secret that the strength and health of tomato seedlings depends primarily on the microelement composition of the soil. In the early stages of growth, tomatoes especially need minerals such as potassium, calcium and phosphorus. At the same time, their deficiency or excess can adversely affect the condition of tomatoes. So, with a lack of potassium, yellow borders appear on the surface of the lower, old leaves of seedlings, while the leaf plate is deformed, twisting upwards. Over time, these leaves dry up and fall off.
The lack of calcium is reflected in the new, apical leaves of tomatoes. With such an imbalance of the substance, the leaves of the seedlings become pale, twisted. Over time, a lack of calcium leads to leaf fall and death of the plant as a whole.
With an excess of phosphorus, pale spots appear on the leaves of the seedlings, which over time rapidly cover the entire leaf plate. In science, this process is called chlorosis, you can get rid of it by applying complex mineral fertilizers or an ash solution.
Often, tomato seedlings suffer from excess nitrogen. And even if the farmer did not apply nitrogen-containing top dressing, the substance could get into the soil in the process of its formation. So, the soil from the garden could be abundantly flavored with manure in the fall. Not having time to overheat by spring, it contains a large amount of nitrogen, which can “burn” tomato seedlings.
Not enough soil
After seed germination, the root system of tomatoes begins to grow and develop intensively. At the same time, it requires a fairly large amount of soil. So, sometimes, as they grow, the roots of tomatoes fill the entire container with soil, tightly intertwined with each other. This leads to a lack of oxygen, and as a result, seedlings will wilt. So, gradually, first the lower, and then the upper leaves of the tomatoes turn yellow and fall off.
By carefully monitoring the growth process of tomato seedlings, timely transplanting plants into large containers, you can successfully avoid leaf fall due to insufficient soil.
Transplant consequences
Many farmers sow tomato seeds in a single container, providing for the subsequent picking of grown plants in large isolated containers. The picking process itself is carried out in the presence of 1-2 true leaves. At this time, the root system of tomatoes is already quite developed and can easily be accidentally damaged during the transplant process. Such plants with a defect in the root system take root for a long time, experience stress and bleat. Their growth slows down significantly. With serious damage to the root system, yellowing and falling of the leaves of the seedlings can also be observed. It is worth noting that overgrown tomato seedlings can be tightly intertwined with roots, and then during the transplantation process they will need to be torn apart, thereby harming the plants.
The problems associated with root damage are also relevant for tomatoes that have been planted in the ground. That is why it is preferable to use peat pots for growing tomato seedlings, the plants from which do not need to be removed during transplantation. From plastic containers, tomato seedlings should be taken out very carefully, keeping a clod of soil on the vine.
disease
The most common disease of tomatoes is late blight. This ailment provokes a fungus that can initially affect one bush, and subsequently spread to all closely spaced cultures of the nightshade family.
Late blight can affect not only adult plants growing in open ground and greenhouses, but also tomato seedlings. Infection can occur due to the recycling of untreated containers, as well as garden soil without proper preparation. In addition, late blight fungus can be found directly on tomato seeds.
Tomato disease manifests itself 10-15 days after infection. At this time, dark, sometimes gray-brown spots form on the leaves and stems of tomatoes. In the presence of high humidity in the room, late blight is also evidenced by a “fluffy” white coating on the back of the sheet. The initial stage of late blight may not be noticeable to the farmer at all, while spreading to nearby tomato seedlings. However, over time, the leaves of tomatoes begin to become completely covered with dark spots and fall off.
For the prevention and treatment of tomato seedlings, special chemicals can be used. However, their use should be limited in living rooms. For preventive purposes, you can use spraying with whey, the acids of which inhibit the development of the fungus.
Knowingly, it is possible to protect plants from phytophthora by processing all the elements involved in the process of growing seedlings:
- Tomato seeds must be treated with a solution of potassium permanganate or wood ash before sowing.
- Soil from the garden must be subjected to heat treatment. To do this, a container with earth is placed in an oven with a temperature of 170-2000C for 1,5-2 hours. This will kill all pathogenic bacteria, fungus and parasite larvae.
- Plastic containers in which seedlings were previously cultivated should be disinfected. For these purposes, you can prepare a solution of bleach, which must be mixed with water in a ratio of 1:10.
Thus, it is easier to prevent the situation with the development of late blight than to save tomato seedlings affected by the fungus in every possible way. For more information on how to prevent and treat this disease, see the video:
Conclusion
Tomato seedlings are the result of the hard, painstaking, daily work of the farmer and it is very disappointing when, for any reason, the leaves of young plants begin to turn yellow and fall. However, by noticing the disease in time and determining its cause, you can prevent the further development of the problem and maintain the health of the tomatoes. Timely, accurate diagnosis largely depends on the knowledge of the gardener. That is why everyone, even a novice vegetable grower, must have a certain, constantly replenished store of knowledge based on scientific research, the experience of professional and competent farmers.