Why hydrangea leaves turn red - what to do with the plant
Content:
Hydrangea is resistant to diseases and pests, at least most varieties cultivated in Russia. However, sometimes problems arise when growing this crop. One of them is the reddening of the leaves. The cause of problems can be a violation of the rules of plant care, the development of diseases or pest attacks. Compliance with preventive recommendations will help to avoid this. So why the leaves of the hydrangea turn red is described in detail in this material.
Why do hydrangea leaves turn red
Many people are interested in the question of why the leaves of the hydrangea turn red. There are many factors that lead to this problem.
Insufficient acidity of the soil
The reason for the reddening of the leaves in paniculate hydrangea may be insufficient acidity of the soil. The optimal parameter for this culture is considered to be about pH 5, although many species grow well in slightly acidic and even neutral soil.
If we are talking about initial care, the plant still needs to be systematically fertilized with organics or minerals. Mulching of the soil is of no small importance.
Damage to the root system
If the leaves of the hydrangea turn red, the reason may be a violation of the rules for transplanting the culture, which led to damage to the root system. When such signs appear, measures must be taken immediately to restore a healthy appearance to the culture. Thanks to this, she will be able to grow and develop normally.
Excessive watering
If only the edges of the leaves dry and turn red in the plant, excessive watering can be suspected. In such a situation, it is necessary to reduce the amount of soil moisture.
It should be borne in mind that a similar symptom is observed with a lack of potassium.
Rooting a seedling in summer
Novice flower growers often root hydrangeas in the summer. Doing this is strictly prohibited. Aggressive sun can lead to red foliage and other problems.
It is recommended to plant a crop in spring or autumn. This can be done before the start of sap flow or before the onset of a dormant period.
Sunburn
Hydrangea tolerates harsh climatic conditions and does not suffer too much from the heat. However, in hot weather, be careful. Redness of large-leaved hydrangea can be caused by prolonged exposure to direct sunlight. Also, the problem is often associated with watering the bush during the day - as a result, the culture gets burns.
Diseases and pests
The following diseases can lead to the appearance of red foliage on hydrangea bushes:
- Chlorosis. This pathology is caused by metabolic disorders.The change in leaf color is associated with iron deficiency. In this case, the foliage becomes lighter, and the veins darken. Spraying with iron chelate, Agricol, Ferovit will help get rid of the disease. For the prevention of chlorosis, hydrangea must be fertilized with products containing iron.
- White rot. The defeat begins with the roots of the bush - they begin to rot. When young shoots are damaged, they become darker. Then rot and plaque appears on the leaves. Fungicides will help to cope with the disease - in particular, Fitosporin.
- Gray rot. The disease is accompanied by the watery tissue of the plant. In a drought, they die off and crumble. Coping with the disease is very difficult. First, it is necessary to remove the damaged fragments, and then spray the bush with Fundazol or Skor.
- Powdery mildew. In this case, the leaves and stems are covered with oily spots, which then darken. At the initial stage of the development of the disease, it is worth spraying the culture with a solution of copper sulfate. In difficult situations, fungicides must be used.
- Septoria. The disease is accompanied by the appearance of rounded brown spots on the leaves. In this case, the edges have a darker color than the central part. As the disease progresses, there is a risk of damage to stems and cuttings. Treatment should be carried out with preparations containing copper.
- Rust. In this case, the leaves are covered with a rusty bloom. The disease is caused by an excess of nitrogen in the soil. Spraying will help to cope with the disease. To do this, you need to mix 20 g of copper and 5 liters of water.
Also, reddening of hydrangea leaves can be caused by pest attacks. Common parasites include:
- Snails. They most often affect the culture in the shade, with a strong thickening of the plantings. Snails consume buds, leaves, young stems. The mechanical method will help to cope with pests. You can also use chemicals.
- Spider mite. When the culture is damaged, yellowish spots with a marble pattern appear. If you do not take action in time, the foliage will dry out and fall off. Chemicals will help to cope with the problem. Initially, a soapy solution may be sufficient.
- Aphid. These pests feed on the sap of the plant and contribute to the spread of fungal infections. Most often, they settle on the lower leaves, which turn yellow and crumble. To deal with aphids, you can rinse the bush with soapy water. In advanced cases, Akarin, Fitoverm are used.
- Gall nematode. These pests attack the roots of the crop. They can cause blistering in this area. Subsequently, decay processes begin. It is very difficult to spot parasites as they affect the underground part of the plant. But if all other possible causes have already been ruled out, only the nematode remains.
What to do if the leaves of a panicle or other hydrangea species turn red
Reddening of the leaves on the bushes requires immediate attention. First, you need to establish the reasons. If this is not done, the problem will not be resolved.
The appearance of brown spots on the leaves indicates infection with a fungal infection. Fungicides - Oxyhom, Fundazol, Hom will help to cope with it. In this case, it is necessary to process the leaves from both sides. This is done 2 times with an interval of 2 weeks.
If fungal infections are detected, preventive measures should be taken every year. In early spring or autumn, biofungicides should be used. A mixture based on Gamair and Alirin is highly effective.
Other ways to solve problems depend on the cause of the appearance of redness:
- with an excess amount of moisture, it is necessary to reduce the frequency of watering;
- in extreme heat, provide protection from the scorching sun;
- check the parameters of soil acidity;
- Apply mineral and organic products once a season.
In winter and summer, the beds should be covered with a mulch layer. This will help to achieve optimal temperature performance.
Feed for hydrangea that has red leaves
When the foliage turns red due to depletion of the soil, it needs to be fed. Violation of acidity parameters prevents the absorption of vitamins, micro- and macroelements.
To improve performance, you can use an effective folk method. To do this, add 1 teaspoon of oxalic or citric acid to 10 liters of water. The resulting solution is recommended to be used for watering the culture. It should be borne in mind that if the root system is damaged, this method is prohibited.
If the reddening of the foliage is associated with damage to the root system, it is worth using a remedy that activates its development. It is recommended to use it 3 times a month. In this case, the bushes should be well watered.
Preventive measures to prevent the appearance of red leaves
To avoid the emergence of problems, you need to strengthen the culture. This will help avoid the development of diseases and pest attacks. For preventive purposes, you must perform the following actions:
- Plant the plant in partial shade. When growing hydrangeas in indoor conditions, it is enough to remove it from the scorching sun, since it does not reflect well on the state of the leaves.
- Avoid drying out. Hydrangea is considered a water-loving plant and requires high-quality watering. In the heat, it should be watered at intervals of 2 days.
- Select the correct soil composition. A light soil with high acidity is suitable for a plant.
- Fertilize correctly. At the end of spring, nitrogen agents should be used, in summer - phosphorus and potassium, in autumn - phosphorus.
- Carry out wood processing. With the arrival of spring, it is recommended to use a solution of copper sulfate.
Red hydrangea leaves can be associated with a variety of factors. To cope with a problem, you need to identify the causes and provide the culture with the right care. Prevention of the development of diseases and pest attacks is of great importance.