Solving the problem of yellowing pepper seedling leaves once and for all

A healthy pepper plant, whether seedlings or already transplanted to a permanent location, delights with its greenery, beautiful leaves, and stocky stems. The appearance of yellowing on the leaves is a sign that something is wrong, and it's important to investigate the cause of the color change.

Sometimes cotyledons and some lower true leaves fall off. This is usually caused by natural processes and is no cause for concern. However, if the leaf blades change color and wilt, the plant stops growing, or dries out, then the situation needs to be addressed immediately.

Reasons

There can be various reasons why the leaves of the heat-loving and capricious Bulgarian lily change color, dry out, and fall off. Stress during transplantation, improper growing conditions, and poor agricultural practices can all lead to yellowing and leaf drop. It's important to quickly identify the cause and then take all necessary steps to restore the plant's health.

Problems with the root system

The tomato is a relative of the pepper in the nightshade family. This has led to some similarities in cultivation techniques, but at the same time, the two crops have differences.

Peppers have a very fragile root system, and their fibrous roots can be easily damaged. Therefore, unlike tomatoes, peppers are difficult to transplant, and adaptation takes a long time. Many gardeners prefer to transplant their plants rather than transplant them to avoid damaging the root system.

When characteristic spots appear, you should first check the condition of the roots.

The changes are caused by:

• root damage;
• poor development (due to insufficient container volume or, conversely, due to excess space);
• intensive root growth (formation of a tangled ball, bending of roots, due to which some do not receive the required amount of nutrition and die);
• loosening of the soil and, as a consequence, deformation of the roots.

What needs to be done? Carefully remove a seedling with yellowed leaves from the soil and inspect the roots. Healthy roots are white; if black or brown roots are noticed, they are already damaged and dying. A root stimulant should be used to promote regeneration, but only if the damage to the root system is minor. If almost all the roots are brown, it is unlikely that the plant will be revived.

The intertwined root ball will need to be straightened out, for which it is best to place the plant in water.

When doing this, you need to spread the pepper very carefully, lightly touching the roots and guiding them into the desired position. Once everything is spread out, return it to its original location, compacting the soil slightly, and continue to monitor its condition. Usually, with healthy and already spread roots, the pepper quickly takes root, begins to grow, and produces new leaves.

To avoid putting unnecessary stress on your peppers, avoid transplanting them. Instead, plant them directly into individual small containers, then transplant them into larger pots. This method is gentler on the plant's root system without slowing down the seedlings' growth.

Nitrogen deficiency

Another common cause is nitrogen deficiency in the soil. This component is essential for the nutrition of garden crops; plants actively absorb it from the soil, and a deficiency immediately affects the health of the plants.

This manifests itself as yellowing of the leaves, with the color change occurring from the main vein to the edges of the leaf blade. At first, the leaves turn pale green, gradually rot, and fall off. The solution: prompt nitrogen fertilization, but be sure to follow the recommended dosage.

Ammonium nitrate is commonly used, diluted in water and gently watered at the roots of the peppers. The recommended dosage is about a tablespoon of fertilizer per bucket of water. Urea can also be used, but foliar feeding by spraying the leaves is more effective.

For seedling feeding, use Azogran (one granule per seedling), ready-made fertilizers such as Uniflor-bud, Aurum-S, or Florist. Products such as Kemira and Agricola for nightshade crops are also excellent. All products should be used according to the instructions.

Insufficient watering

Peppers, like many other garden crops, are equally harmed by both drought and overwatering. This problem is especially common when grown in peat pots. In such containers, moisture levels are very difficult to control, the root system often lacks water, and this instability leads to yellowing leaves and stunted growth.

This crop, both when growing seedlings indoors and in its permanent location, requires regular watering, avoiding overwatering. It's generally recommended to water the seedlings when the soil begins to dry out, ensuring the soil is moist but not stagnant. This is done approximately every 4-5 days, but this depends on the growing conditions.

Excessive soil moisture leads to yellow leaves, crop diseases, and stunted growth. In a greenhouse or garden bed, it's advisable to mulch with straw, hay, or compost. This will not only balance the soil's moisture levels but also eliminate the need for labor-intensive weeding and soil loosening.

Nutrient deficiencies

Peppers will only grow strong and healthy if they receive proper, nutritious nutrition. If there are any deficiencies, the plants will immediately notice them in their appearance.

One type of deficiency—nitrogen starvation—was already mentioned above. But leaves can also suffer from a lack of certain other elements:

• calcium;
• potassium;
• gland.

If the plant's diet is deficient in calcium, yellow spots will appear on the leaf blades, and the growing tip will begin to rot and die. Plants should be fed with ash, excluding nitrogen and potassium. All fertilizers should be applied at the correct rate, as excess amounts are possible. Excess calcium can also cause problems, so a nitrogen-containing fertilizer should be applied.

Have you noticed that the leaf edges are changing color and drying out, while the center and main vein remain green? This is a sure sign that the plant is suffering from a potassium deficiency, so a potassium-containing fertilizer is recommended.

Peppers grown in soils with high clay or lime content often suffer from iron deficiency. This manifests itself as irregular spots on the leaves, yellowing of the leaf margins, and leaf dieback. Iron deficiency can be corrected by applying iron chelate fertilizers. It is also recommended to add dolomite flour to such soils before planting.

Violation of care conditions

Heat-loving peppers are often considered a finicky crop. To achieve a high yield (especially in risky farming zones), it's essential to create comfortable conditions for the plants.

Meanwhile, in most regions of Russia (except the south), peppers are grown from seedlings, which involves picking the plants, caring for them indoors, transplanting them to their permanent location, and then caring for them in a greenhouse, under cover, or in a garden bed. And everywhere, peppers require warmth, good lighting, regular watering, and fertilizing.

Violation of certain parameters often leads to stunted plant growth, leaf coloration changing from deep green to yellow, and then leaf drop. The room temperature may be acceptable for peppers, but the soil in containers near the windowsill may be cold. The plant will quickly react to this by yellowing and dropping its leaves.

When growing indoors, it's important to maintain a stable temperature: 23ºC to 25ºC, avoiding significant drops. At night, 18ºC to 20ºC is sufficient for seedlings.

Leaves can turn yellow due to both insufficient light and sunburn. Therefore, it's crucial to provide seedlings with supplemental lighting during the initial growing period, and then protect them from excessive sunlight. Shading may also be necessary after picking (if planned) and after transplanting.

In regions with short summers, greenhouses, shelters with arches, and tunnels are required for peppers. Careful soil preparation is also essential for a good harvest, so a nutritious, high-quality soil mixture is selected for both seedlings and the soil in the greenhouse and garden beds is fertilized according to regulations.

Acidic soils require liming, and dolomite flour should also be added when tilling the soil in the fall. To improve soil looseness, it is recommended to add humus, rotted manure, compost, and ash.

When growing this crop, use mulch. Hay, straw, bark, rotted peat, humus, compost, and buckwheat husks are all suitable. And be sure to practice crop rotation to prevent infections and pests.

Reaction to transplantation to a permanent location

When transplanting peppers to their permanent location, it's best to choose a cloudy day or work in the evening. Transplanting is a significant challenge for a plant, so to make the process as easy as possible, we recommend the following:

• About 10-12 days before, harden the seedlings, gradually accustoming them to fresh air and new living conditions;
• plant the plants at a stage when the roots have not yet completely filled the container;
• use the transshipment method to avoid deforming the roots and planting plants with a whole lump of earth;
• Use convenient paper cups that allow you to transfer the product to a permanent location without damage.

Ideally, the soil in the greenhouse or garden beds should be similar in composition to the soil in which the seedlings were grown indoors. Planting times vary by region. Typically, in a greenhouse in the temperate zone, the crop is planted as early as mid-May, while in colder regions, planting should begin as early as early June.

When doing this, be sure to take into account the soil temperature, which should be between 14ºC and 16ºC. It is recommended to cover the transplanted plants with non-woven material to protect the peppers from sudden temperature changes, bright sun, and possible cold snaps. The material is later removed, and in August, when cold nights arrive and the dew falls, it can be reused.

Pest infestation

Another cause of pepper leaf discoloration is pests. Young seedlings are a tasty morsel for aphids and spider mites. These insects are the ones that most commonly attack seedlings indoors.

In a greenhouse or under cover, the range of pests expands, and various infections can also cause yellowing. Therefore, preventative measures and proper agricultural practices are essential.

If you notice yellowing of some leaves, curling of the leaves, or the appearance of cobwebs between the leaves—all of which are signs of damage to peppers by aphids or spider mites—you must immediately take decisive action.

1. If there are only a small number of insects, they are removed from the leaves by wiping the leaf blades with a soap solution.
2. Peppers are sprayed with infusions of garlic, ash, and tobacco.
3. Infusions of chamomile, dandelion, and yarrow are used for processing.

All these folk remedies are effective only for minor plant damage, if the insects are few in number. If pests appear en masse, chemical treatments will be necessary, following all instructions.

Aktara, Inta-Vir, Iskra, and other products available in specialist stores are suitable. In addition, biological products such as Fitoverm and Strela are also effective.

By identifying the cause of yellowing and leaf drop and quickly eliminating it, you can get healthy, full-fledged plants and avoid crop losses.

Reviews

Inna, Leningrad region

After transplanting, the lower leaves of my pepper seedlings started turning yellow and falling off. I read that this was possible, but I'd never had this happen before. I bought Fitosporin, poured the solution into a spray bottle, and treated the plants for several days. Everything seemed to have cleared up; the remaining leaves were green and didn't fall off or turn yellow again. I had a good harvest.

Nika, Chelyabinsk

For two years, my peppers turned yellow in the spring, and I kept losing seedlings. A relative came to my rescue; fortunately, she always plants a lot of vegetables. But then I finally decided to investigate the cause and discovered that it was most likely due to poor soil. I seemed to have fertilized it and watered it with potassium permanganate. But something didn't seem to be working, and the tomatoes didn't either. So, for the third year now, I've been buying some soil from the store (I use Violet), adding ash, humus, and perlite, mixing it all together, and growing the grove in that soil. Everything has returned to normal, the seedlings are healthy, and there are no yellow leaves at all. So, the soil could also be the issue.

Vitaly, Petrozavodsk

Last year, the seedlings on the windowsill suddenly started turning yellow in May. And there was still almost a month left before planting. There seemed to be no pests, the soil was good, and there was enough nutrition. We consulted with friends who are long-time gardeners, and they suggested covering the peppers from the sun after lunch. They're on the sunny side, and the sun beats down there in the afternoon, so the plants must have gotten too hot. We watered them normally, but the heat was killing them. We started covering the window with net curtains, then sprayed them with epin. Everything's fine now; apparently, they really were too hot there. This year, we'll take everything into account.