Why did the lower leaves of tomatoes turn yellow after planting?

Many gardeners, especially beginners, ask questions about how to save tomatoes if the lower leaves turn yellow after planting. The concern is fully justified, since tomato is a capricious culture, susceptible to fungal and viral diseases, and also strongly reacts to the shortcomings of a number of elements in the soil. Untimely measures taken to address problems often lead to the loss of seedlings and crops.

To correctly determine the cause of yellowing of tomato leaves after planting, it is necessary to assess the nature of the lesion. Often inexperienced vegetable growers begin to spray plants in a panic with everyone in a row, only aggravating the situation.

When there is no cause for concern

It should be noted that a healthy strong bush can shed the lower leaves as unnecessary, first of all getting rid of the cotyledons. This period may coincide with planting in the ground or greenhouse.

If after transplantation the root system is injured, then the plant redistributes resources to the growing point, taking food from the lower part. But at the same time, the plate turns yellow evenly, no pronounced spots and foci are formed.

Lack of elements

The reason why the lower leaves of a tomato turn yellow is not always disease. The top of the plant, with a lack of nutrients, begins to pull them from below, after which the leaf plates weaken and dry out.

The need for feeding with this or that element can be determined by a number of signs.

• Nitrogen: the leaf blade turns yellow evenly, while the plant itself looks fragile, the stem is thin. You can help by watering with a solution urea (30 g per 10 liters of water).
• Potassium: the veins remain green, the lesion begins at the edges, along which a brownish border is formed, the leaf rolls up and gradually dries up. The reason may be too acidic soil, since in this case potassium is used to deoxidize it. The lack of an element is made up for with potassium nitrate, diluted in a proportion of 1 tbsp. spoon on a bucket of water.
• Magnesium: according to external signs, magnesium starvation of a tomato resembles potassium, but there is no pronounced folding of leaves. The veins remain green, and the yellowness around them appears as a small mosaic. The problem is solved by spraying with magnesium nitrate (5 g per 10 liters of water).
• Molybdenum: It is expressed in the appearance of speckled chlorosis, in which the lower leaves of a tomato are gradually covered with brownish blotches, after which they turn yellow and curl upward. For treatment, top dressing is used with a 0.02% solution of ammonium molybdate (2 g per 10 liters of water).

With a lack of phosphorus, the lower leaves of a tomato also suffer first, but they do not turn yellow, but purple.

Advice for those who prefer natural fertilizers: nitrogen deficiency can be replenished mullein infusion, chicken droppings, granulated biohumus, compost. Potassium and phosphorus will provide wood ash and humates.

Violation of the irrigation regime, lighting and poor soil quality

The reason why the lower leaves of a tomato begin to turn yellow after planting may be the soil. The roots of the plant require loose and moderately nutritious soil, enough oxygen must be supplied to them. If the soil is dense, caked, covered with a crust, then the suction function is inhibited at the roots, the tomato begins to save food, starting from the bottom. A solution to the problem is to gently loosen and moisturize. Ideally, the tomato is best transplanted into a lighter potting soil.Too high acidity also leads to the death of the lower layer of foliage.

Violation of the watering regime also has a detrimental effect on the plant. With a regular excess of moisture, the air exchange of tomato roots is disrupted, the soil sour. The lower leaves of a tomato also turn yellow when dried out, since nitrogen and phosphorus from them move to the stem. It happens that watering is done in hot weather, water gets on the leaves, as a result of which there is a burn, white spots.

Often, seedlings are kept at home for a long time or in too cramped containers, which leads to the formation of a dense lump of roots. This is also the reason why, after being planted in the ground or greenhouse, the lower leaves of a tomato turn yellow and die off. In this case, the roots take a long time to turn around and begin to function normally.

Diseases

If you can cope with a lack of nutrition with several dressings, then diseases, especially viral ones, have to be fought not only with special drugs, but also by changing the microclimate.

"Dropsy" - seedling disease

Gardeners often complain of an unknown disease, in which the lower leaves of tomato seedlings are covered from the inside with small water bubbles. Subsequently, they burst, leaving a yellow dry stain. The defeat begins from the edges, gradually passing to the entire leaf plate. A characteristic feature is that after planting in a greenhouse or in the ground, this phenomenon, as a rule, disappears. It is likely that the reason is the quality of the soil, violation of the lighting and irrigation regime, too stagnant air (especially with double-glazed windows).

Some experienced breeders recognize in this disease edema (oedema) - dropsy of leaves, more characteristic of peppers. But there are differences: with oedema, not bubbles appear, but growths that do not burst or erase (moreover, on all leaves), and in the case of tomatoes, it is worth sliding your finger along the back of the leaf plate, as all pustules flow out.

The disease is not contagious, since it is a consequence of a violation of the metabolic processes of a particular plant. Bushes of other varieties standing next to the affected tomato may not be affected - it all depends on how comfortable their root system is. Therefore, it makes no sense to arrange "quarantine" If all tomatoes are of the same variety and are planted in equal conditions, then everyone will get sick. Gradually, as the bubbles burst, the leaf becomes stained, turns yellow and dries up.

Treatment methods:

• arrange seedlings less often, ensuring good air circulation and ventilation;
• if there is not enough sunlight, then it is recommended to purchase a phytolamp;
• let the soil dry, then transplant tomatoes or sprinkle soil with vermiculite or agroperlite;
• protect the container with the plant (if it is transparent) from direct sunlight to avoid overheating of the roots (you can wrap it in newspaper).

The main reason why dropsy appears is considered to be overflow, as well as too dense soil.

Fungal lesions

It happens that after planting in the ground or greenhouse, in perfectly healthy tomato seedlings, after a while, spots are found on the lower leaves, which, merging, lead to their yellowing and drying. It is likely that the spores of the fungus that caused the septoria disease (white spot) got on the plant. Typical features: randomly spaced gray specks with a light halo.

Brown spot also begins its development from the lower leaves of tomatoes. The plant is covered with brown spots with lemon edging. The lower leaves also turn yellow from cladosporium.

Fungus control measures:

• decrease in air humidity;
• soil and plant treatment with antifungal agents (Bordeaux mixture, "Fitosporin");
• regular ventilation;
• timely removal of the lower "waste" leaves.

It is wiser to prevent fungus and bacterial infection with the help of preventive measures, treating with Fitosporin every two weeks.The basis of the drug is the spore culture of Bacillus subtilis, which inhibits the development of pathogens. The main plus - "Fitosporin" is completely non-toxic. Spraying can be carried out at any stage of growth.

Advice

Treatment with "Fitosporin" should be carried out in cloudy weather, since the bacteria dies in bright sunlight.

As a rule, the reasons why only the lower leaves of tomatoes turn yellow after planting are easily eliminated. Serious disease usually affects the entire plant, including the tops and stems. If there are no signs of fungus, then you should feed the bush and optimize the conditions for its growth.

A good tool for strengthening the immunity of tomatoes and other crops is the drug "Epin" (adaptogen). It will help to cope with diseases, as well as neutralize their consequences.