For what reason cabbage seedlings turn yellow
A particularly important step in growing cabbage is getting seedlings. With inappropriate care and in violation of agricultural technology, cabbage seedlings often turn yellow. Considered how to act in such a situation.
Causes
Most often, cabbage seedlings turn yellow if low-quality seed is used. He may be infected with diseases. Seedlings of cabbage very often turn yellow also due to the introduction of a substrate with pathogens into the soil.
- Lack of moisture or waterlogging. With a moisture deficit, the plant does not receive a sufficient amount of nutrients from the soil, growth slows down. Excess watering leads to the formation of a dense crust in the soil. It interferes with the access of oxygen to the root system. This leads to root rot and the appearance of yellow leaves.
- Inappropriate seed treatment. For a cabbage crop, an important element of cultivation is seed hardening. It is carried out to ensure the resistance of the plant to various diseases.
- Lack of nitrogen and potassium. Due to the deficiency of nitrogen and potassium in the soil, the vegetable crop stops growing, and a yellow tint appears on the leaves.
- Disembarkation dates. Seedlings are planted in open ground when the cabbage has 3-4 true leaves. The height of the plant is not less than 10 cm. The approximate time of planting is May or June, the age of the seedlings is 40-45 days.
- Soil selection. If you choose an unfavorable soil, the seedlings will begin to wither and change color. It should be with enough fertilizer, ash and sand.
- Temperature regime and location. It is not recommended to leave a container with seedlings in a place where direct sunlight and ventilation is not carried out. If you leave the pots with seedlings in a room with an elevated temperature, they will stretch out a lot, and the root system will not have time to develop. This leads not only to the yellowness of the seedlings, but also to the death of the entire plant.
With inappropriate watering, the lower leaves begin to turn yellow, and over time the whole plant. It is necessary to start treating seedlings only after determining the main cause.
How to fix the problem
If cabbage seedlings turn yellow, you need to act immediately. Timely action can save the plant.
room | Agrotechnical event | Mode of application |
1 | Watering | Abundant watering is required. It is recommended to moisten the soil 2-3 times a day. Make sure that the ground does not turn sour due to waterlogging. |
2 | Mulching | Keeps the soil loose, weeds grow less frequently. Sawdust and bark are well suited for mulch, with a layer of 2-7 cm. Peat and compost protect the soil from washing out nutrients and weathering. |
3 | Temperature and light | After germination, cabbage seedlings need a place with a temperature of 8 ° C to 12 ° C for 7-13 days. Cabbage is a very light-loving plant, so it needs bright lighting during the seedling period. |
4 | Open ground transplant | Cabbage seedlings turn yellow in case of non-observance of the rules for planting in a permanent place. If only the lower leaves have turned yellow, do not worry. But if the whole plant has changed the color, then nitrogen fertilizers should be applied. In order for the plants to take root in the open field faster, it is recommended to choose the soil on which the cucumbers, carrots and tomatoes grew. You need to plant according to the scheme: in a row after 25-30 cm, between rows 35-40 cm. |
Fertilizers
Cabbage seedlings turn yellow with an insufficient amount of dressings, both foliar and root. Top dressing should be moderate. It is necessary to process not only the lower leaves, but also the soil in which the vegetable crop is grown. Fertilizers with organic or mineral nitrogen fertilizers should be applied only in spring or June. For this, ammonium nitrate is used, it contains 34% of available nitrogen. 4 g of the substance is mixed with 1 liter of water. You can also add 4 g of superphosphate and 1 g of potassium chloride to the solution, but at the same time reduce the weight of ammonium nitrate to 2.5 g. Add such a mixture to the soil, a week after picking.
Saplings may turn yellow from a lack of trace elements in the soil: phosphorus, iron, potassium. A few days before planting in the open ground, broccoli, white cabbage and cauliflower are fertilized with a complex of feedings. To do this, you need to mix: 2 g of potassium chloride, 7 g of superphosphate and 4 g of ammonium nitrate per liter. Wood ash and lime are added to the soil for the resistance of the vegetable crop to weather conditions.
For the preservation of moisture and a sufficient amount of useful elements in the soil, an infusion of mullein is used. To do this, you need to insist 0.5 liters of the substance in 10 liters. water for 2-3 hours.
Diseases of cabbage seedlings
Young plants are most often affected by various diseases. If symptoms are detected, prophylaxis or appropriate agrotechnical measures should be carried out.
room | Disease | Ways to fight disease |
1 | Blackleg | Sign - blackening of the stem and root collar, which leads to a change in the color of the leaves and the death of the entire bush. For prevention, loosening and mulch are used. Sprinkle the top layer of soil with ash and lime. The weakest plants must be removed. |
2 | Keela | Acts as an outgrowth at the root. They appear due to high soil moisture, late planting of seeds and high acidity of the soil. Diseased plants cannot be cured, they are removed. The soil is disinfected with a solution of potassium permanganate. The mixture is prepared from 10 liters of water and 5 g of the substance. |
3 | Fusarium | Appears due to a small amount of moisture and due to hot days. Affected plants are immediately dug up together with the roots and destroyed. The soil is disarmed with a mixture of copper sulfate. To increase the plant's resistance to fusarium, the bush is treated with Agat-25, Immunocytofit preparations. |
Most of the seedling diseases cannot be treated, therefore, preventive agrotechnical measures and hardening should be carried out before planting seeds and during growing seedlings.
Seedling pests
If cabbage leaves begin to curl, dry out and turn yellow, then this may be a sign of the presence of pests:
- aphid;
- cruciferous flea;
- spider mite;
- cabbage moth;
- slugs.
In the fight against spider mites, the leaves are washed under running water and sprinkled with a thin layer of wood ash or tobacco dust. Using a soap solution, a mixture of iodine with milk or tomato tops, you can get rid of cabbage aphids. Spraying with wood ash is used against moths.
Cruciferous fleas are afraid of vinegar solution, chicken droppings, or celandine. And slugs and snails of mustard powder, infusions of garlic or onions.
Rooms | Solution | Preparation |
1 | Soap solution | You need to mix 1 liter of water and 4-5 tablespoons of liquid soap or detergent. |
2 | A mixture of iodine with milk | To do this, use 1 liter of milk, 9 liters of water and 10 drops of 5% iodine. |
3 | Tomato tops | 4 kg of tops are crushed and filled with 10 liters of water. Bring the mixture to a boil, settle for 5 hours and filter. 50 ml of liquid laundry soap is added to the solution. And dilute 1 liter of solution with 3 liters of water. |
4 | Onion infusion | 300 g of onions are poured over 2 liters of boiling water and left for 24 hours. Filter, add 30 ml of liquid soap and 10 l of water. |
Pests have a detrimental effect on plant growth and fruit appearance. Therefore, when insects are detected, preventive measures should be taken immediately.
Conclusion
Almost every stressful situation caused by a violation of the rules of care causes yellowing of the leaves, especially in the lower part of it. Therefore, in such cases, you need to figure out what could cause stress on the vegetable crop, and then take the necessary measures.