Why do pumpkin leaves turn yellow?

Growing pumpkins in a personal or summer cottage is associated with the characteristics of the culture. Pumpkins have a long growing season that can stretch up to 150 days. During the formation and ripening of fruits, the culture consumes an increased amount of nutrients from the soil, so it needs regular top dressing. Pumpkins turn yellow for various reasons: sometimes this may be due to a lack of useful elements, sometimes it is evidence of disease.

Possible Causes of Yellowing Pumpkin Leaves

Pumpkins are grown by seedling and seed methods. It depends on the characteristics of the variety, as well as on the climatic conditions of the region. In the southern territories, seeds are sown in open ground, but in the north of the country only the seedling method is used. The reason for the yellowing of pumpkins may be hidden in the violation of planting technology, the lack of pre-sowing preparation, and much more.

The problem of yellowing leaves is easy to deal with if the cause is identified in a timely manner and the necessary measures are taken. At the growing stage, the seedlings turn yellow due to lack of light. To provide the seedlings with optimal conditions for growth, they are satisfied with a daylight hours lasting at least 10 hours. In the absence of natural light, lamps are installed above the seedlings.

Weather

One of the main reasons why pumpkins turn yellow can be temperature fluctuations. This natural factor is difficult to influence, but you can help the plant adapt faster. The pumpkin turns yellow if there is a sudden change in temperature:

• the air temperature during the day dropped to +10 °C;
• a long drought gave way to a sharp cold snap;
• there were frosts at night.

With the onset of return frosts, the pumpkin turns yellow after freezing. As a rule, this applies to the tips of the leaves and those lashes that are on the ground.

Nutrient deficiency

Lack of nutrition is one of the most important items on the list of causes. This is a unique culture, for the full development it needs fertile soil, from which it receives the maximum amount of nutrients.

At different stages of development, the culture needs to be supplemented with a variety of top dressings. To prevent wilting and yellowing of the leaves, a special schedule of necessary feedings has been developed for the pumpkin:

1. After planting, the bush is fed when the 5-6th leaf appears, organic fertilizers are applied.
2. Before flowering, fertilize with organic fertilizers and mineral mixtures with a high potassium content.
3. When flowering, additional basal top dressing with potassium compounds is necessary.
4. During the fruiting period, pumpkins need to be supplemented with potassium, phosphorus, and calcium.

These are the main top dressings that are required. If the soils of the region in which the pumpkin is grown are not rich in nutrients, then top dressing is carried out more often.

The green mass is treated foliarly, vitamin formulations are sprayed from a spray bottle.

disease

Pumpkin is considered resistant to many diseases, but if it becomes infected, then it can be quite difficult to cure it.

Among the dangers that lead to the fact that the pumpkin turns yellow, a special place is occupied by fungal infections. They develop rapidly, the source of the development of the disease is difficult to detect. Infection begins deep in the soil: the fungus primarily affects the root system.

• Bacteriosis. Begins to show a slight yellowing of the leaves, which quickly turn brown. Spots appear on the reverse side of the plates, then they dry. The infection captures the entire plant: the fruits do not develop according to the usual scenario, but begin to deform and become covered with dry spots;
• Mučnistaâ rosa. One of the most dangerous diseases for various types of vegetable crops. On a pumpkin, it begins to appear with the appearance of a whitish coating. As a concomitant symptom, the green mass turns yellow. The lashes gradually wither and dry up. This leads to a complete loss of pumpkin immunity, therefore, at this stage, insects and other diseases can join the main disease;
• White rot. The first stage begins with a slight yellowing of the leaf plates along the edges, then they are covered with a white bloom. At the next stage, the plaque becomes slimy, rotting begins. White rot spreads throughout the plant: stems, leaves and fruits are affected;

  

• Root rot. A characteristic symptom of the disease is yellowing of the lower leaves of the pumpkin. This is due to the fact that the root system is at the stage of decay, the parts of the plant closest to the roots are the first to be affected. The whip gradually turns yellow, starting from the central stem. This is due to the inability of the roots to provide parts of the plant with nutrients and the minimum set of nutrients necessary for growth;
• yellow mosaic. This disease affects young bushes. The leaves turn yellow, curl around the edges. The fruits are twisted during formation, then covered with mosaic spots. Bushes grow slowly, do not respond to additional feeding, because, most often, they are not able to absorb useful elements.

There can be several reasons for contracting fungal infections. These include:

1. Irrigation violations. Overmoistening of the soil leads to rotting of the roots. In addition, watering with cold water may be a risk factor. Plants often start to get sick if they have not been watered for a long time, and then watered abundantly.
2. Non-observance of crop rotation. Planting pumpkins in the same area for several years in a row is excluded. This leads to the depletion of the soil, the loss of protective mechanisms.
3. Spread of the fungus by weeds and insects. When growing pumpkins, it is recommended to weed the plots in a timely manner and ensure that the soil is loosened.

vermin

Pumpkin leaves turn yellow if pests get on the plant.

1. Tick ​​of the web. This is the most common type of driver. It entangles the leaves and stems with cobwebs, feeds on the sap of the plant. This leads to yellowing of the leaves, their gradual wilting. Then the leaf plates dry up and crumble. The peel of the formed fruits begins to crack.
2. Melon Caviar. These insects prefer to settle on the reverse side of the leaf blades. First, the leaves turn yellow, then wither and fall off. Aphid colonies grow very quickly. Egg clutches can be found on all parts of the plant. The fight against aphids can be complicated by the fact that after the removal of adults, invisible larvae remain on the plant.
3. Slugs. Pests appear on a pumpkin in cloudy rainy weather. They begin to eat parts of the plant, as a result of which the remaining ones turn yellow and wither. Slugs are easy to spot on close inspection, but difficult to deal with.

What to do if pumpkin leaves turn yellow

When signs of disease or insect invasion are detected, various agricultural practices are used. Their choice depends on the stage of development of the problem and the state in which the pumpkin is located.

With temperature changes

If the reason that the pumpkins turned yellow is a cold snap, then gardeners advise additionally covering the pumpkin with industrial materials. At the same time, during the time that the pumpkin spends under additional shelter, it is periodically aired, since the accumulation of condensate on the film can damage the plant.

The reason for yellowing can be hot sunny weather. Leaf plates turn yellow and begin to dry out if burns form on them. Direct sunlight, especially on wet leaves, and then intense evaporation of moisture in the hot sun – all this leads to the fact that the entire surface of the leaf turns yellow, and not just its edges. If hot weather with a scorching sun has set in the region, it is better to shade the pumpkins. This method will protect the plant from burns.

With a lack of nutrients

Nutrient deficiencies can be quickly replenished. If the pumpkin turned yellow because of this, then nitrogen-containing complexes are added to the soil to increase the green mass.

At the stage of fruit formation, it is recommended to use potassium chloride and superphosphates.

How to treat diseases

If the pumpkin has turned yellow due to fungal or bacterial infections, control measures include different types of treatment.

One of the methods of preventive work is pre-sowing preparation. Seeds must be treated with disinfectant solutions, hardened, checked for germination. These activities enhance adaptive qualities.

The soil in which the pumpkin is grown must be disinfected if it has grown infected plants in the previous season. Full compliance with crop rotation is necessary. Pumpkin is not planted after zucchini, melons, watermelons. Good neighbors for pumpkins are: tomatoes, carrots, eggplants.

How to treat pests

The best measure to protect a crop from pests is preventive measures. They are carried out at the initial stage of plant development, when the adaptation period is over.

Treatment with decoctions of phytoncidal herbs is considered a good remedy. They prevent the reproduction of aphids, the appearance of a tick.

Insecticides are used to kill emerging pests. Processing, as a rule, takes place in several stages, since after the destruction of noticeable individuals, larvae may remain on the pumpkin.

Slugs must be removed from the leaves of pumpkins by hand, otherwise it is impossible to get rid of them. Then the bushes are treated with solutions of tobacco or laundry soap to prevent their return. For solutions with tobacco, the leaves are infused for several days, then spraying is carried out. For a soap solution, take laundry soap. The chips are dissolved in warm water and sprayed onto the leaves.

Conclusion

Pumpkins turn yellow for many reasons. If you prepare the seed material, as well as process adult plants in a timely manner, then the death of the plant or the loss of part of the crop can be avoided.