Helpful tips on how to save wilting tomato seedlings

Caring for tomato seedlings has its own subtleties – without maintaining the right microclimate, expecting healthy and strong seedlings is pointless. Tomato seedlings can turn yellow and begin to dry out for many reasons, which aren't always easy to identify and eliminate. But if you catch any signs of trouble in young plants early, you can save the future harvest.

Common problems

Tomatoes don't particularly require strict agricultural practices and present no particular challenges during seedling preparation. Compared to other garden crops, tomato seeds have a higher germination rate, and the seedlings are quite hardy and tolerate picking and planting outdoors without issue.

However, seedling development doesn't always go smoothly. Sometimes, due to inexperienced gardeners, tomato seedlings may experience dry leaf tips, or even lose their leaves entirely. A dejected plant appearance is the first sign of care errors that can still be corrected. The most common reasons for tomato seedlings to turn yellow and dry out are:

• insufficient moisture of the soil mixture;
• reduced air humidity in the room with seedlings;
• pest attack or fungal diseases;
• lack of nutrients in the soil;
• insufficiently careful transplantation to a permanent location;
• acidification of the soil mixture;
• sunburn.

If the problem is in the soil mixture

Excess peat in a prepared soil mixture does not always positively impact the speed of seedling development. Sometimes, a large peat content in the substrate can cause leaf blades to change color from green to a faded yellow. In addition to an excess of peat, a lack of sand and perlite can also cause yellowing of tomato seedlings. This causes the soil in the seedling container to compact into a heavy, dense ball with minimal air permeability, preventing proper root development.

Soil salinity can also lead to to yellow and whitish areas on leaf blades Seedlings. Excessive salt levels in the soil mixture can be detected by light-colored streaks on the surface of the substrate in containers with young plants. Salinity occurs when watering with excessively hard and unsettled tap water, as well as when fertilizing too abundantly and too frequently. To reduce salinity, remove the top 3 cm of soil and water with "soft" water. To resolve the problem with the soil mixture, replant the tomatoes in new soil. The substrate should consist of the following components:

• fine river sand, pre-washed – 1 share;
• wood ash – ½ part;
• perlite – 1 share;
• turf soil – 2 parts;
• coconut substrate – 1 share;
• peat or leaf soil – 1 part.

This replacement substrate will improve the condition of tomato seedlings that have turned yellow and begun to dry out. However, such measures can only save young plants if taken promptly. If the leaves on some of the tomatoes have already dried out, they cannot be saved. And the remaining young plants will not be able to develop sufficiently to produce a normal harvest.

Incorrect irrigation scheme

Tomato seedlings require a specific watering schedule: the substrate in the seedling container must be moistened generously, but sparingly, using only settled, soft water at room temperature. Water the seedlings exclusively in the morning or evening, and apply water at the roots to avoid moisture getting on the leaves. Tomato seedlings respond equally well to both overwatering and periods of drought. Stagnant water in the seedling container prevents the root system from receiving sufficient oxygen.

Top dressing

Nutrients in the soil must be present in optimal concentrations. When there is a deficiency or excess of certain micronutrients, tomato seedlings may turn yellow and begin to dry out. To accurately determine what's wrong with young plants, you need to pay attention to a specific list of signs indicating a deficiency of specific elements. The main signs are:

1. Potassium – a deficiency of this element is indicated by yellowing of the leaf tips against the green veins. To solve this problem needs additional feeding potassium humate or potassium sulfate.
2. Calcium – foliage becomes deformed and curls. The upper leaf blades turn yellow, while the lower ones remain green. To solve this problem, apply calcium nitrate.
3. Nitrogen – both leaf tips and veins turn yellow. The lower leaf blades are the ones that turn yellow, while the upper leaves are small. To restore tomato seedlings, they need to be fed with ammonium nitrate, urea, chicken manure, or well-rotted cow manure.
4. Zinc – the lower leaves are pale yellow and discolored. Spray the seedlings with zinc sulfate.
5. Magnesium – when deficient, the edges and margins of leaf blades turn yellow, while the veins become a rich green. This problem can be solved by treating tomato seedlings with magnesium sulfate.
6. Iron – new leaves grow small. The leaf surface becomes yellowish with prominent green veins. The deficiency is corrected by spraying with copper sulfate.
7. Manganese – leaves turn yellow and dry out, then fall off. To correct the situation, treatment with zinc sulfate is necessary.
8. Phosphorus – a micronutrient deficiency is indicated by the seedling's yellow top, compared to the lower part, which has a distinct purple tint. Fertilize with superphosphate extract.

Tomato diseases

Yellowing foliage on tomato seedlings can be caused by bacterial and fungal diseases. These conditions are identified by characteristic symptoms and treatment is prescribed. If the seedlings are not treated promptly, you could lose all of your plants. The most common causes of yellowing foliage include:

• fusarium;
• blackleg;
• rot.

To stop the progression of these diseases, inspect the plants for the extent of damage. Those that cannot be saved are ruthlessly discarded. The remaining tomatoes are washed with a weak solution of potassium permanganate and planted in fresh soil. After fungal and bacterial infections, the container and soil are treated with high-temperature heating.

Preventive measures

The best way to avoid plant problems is to prevent any problems. When purchasing seeds, one of the most important factors is to check expiration dates and choose proven varieties. To prevent any abnormal foliage issues with tomato seedlings, follow proper care and perform preventative measures:

1. In the first period growing seedlings Lighting must be provided for 16 hours. For this purpose, phytolamps are used, which are turned on after sunset.
2. The temperature in the room where the tomato container is located is maintained at 22-25°C. When the first seedlings appear, it should be lowered to 17°C for 7-14 days.
3. It's best to water the first shoots using a spray bottle to prevent the soil from being washed away. When the plants begin to form their first leaves, replace the drip irrigation method with a tray.
4. To protect plants from diseases, it is important to warm the soil when sowing seeds, and treat the seeds themselves with a pink solution of manganese.

Pests that also cause yellowing of seedling leaves are easy to spot on young plants. It's best to remove them from tomatoes early. To do this, add vermiculite or perlite to the soil. Once the plants have been planted in optimally nutrient-rich soil, begin applying fertilizer no sooner than 7 days later, based on the seedlings' appearance. Healthy tomatoes have thick stems, even when small, and their leaves are a vibrant green.