Hydrangea belongs to the category of plants resistant to pests and diseases, as it has high natural immunity. But if the growing conditions are inconsistent, this culture can be affected by chlorosis, which negatively affects the appearance of the plant and can cause death. Therefore, every grower growing hydrangea should know how to deal with this disease, what to do when the first alarming signs appear.
Types of hydrangea chlorosis (viral and non-viral), causes of the disease
Hydrangea chlorosis can be of 2 types: viral and physiological. In the first case, the pests that transmit the infection can provoke the development of the disease. The chlorosis virus can also be transmitted through young seedlings of the culture, so you should carefully examine the plants when buying.
Most often, chlorosis affects young hydrangea seedlings
In the second case, the reason is a violation of the rules of agricultural technology, as a result of which the shrub lacks iron. This occurs in the absence of timely top dressing or as a result of the inability of the roots to absorb it from the soil.
In spring, non-viral chlorosis of hydrangea leaves most often occurs due to sharp changes in night and day temperatures, which negatively affects the plant's immunity. In this case, the roots of the shrub are in cold earth, and the leaves are heated by the active spring sun. This leads to metabolic disorders in the tissues and slows down the process of photosynthesis.
Heavy compacted soil can also provoke the development of chlorosis. As a result of this, the functionality of the roots is reduced, and they cannot absorb iron from the soil in the required volume.
Important! The cause of chlorosis can be mechanical damage to the roots, as well as close proximity.
Symptoms of chlorosis of hydrangea leaves
The disease has distinct signs that are not difficult to identify. First of all, the leaf plates begin to fade, but at the same time the veins remain saturated green.
Other symptoms of the disease:
- the size of young leaves is significantly reduced;
- the edges of the plates begin to dry out and curl up;
- buds fade without opening;
- inflorescences fall;
- leaves gradually lose turgor;
- the tops of the shoots dry out;
- buds, flowers are deformed;
- rot the roots.
When chlorosis leaves unnaturally brighten leaves
If at least some of the listed symptoms appear, it is necessary to carry out treatment, which will allow the shrub to recover. Otherwise, the plant alone will not be able to cope with this problem.
For reference! Most often, hydrangeas suffer from non-viral chlorosis, namely from a lack of minerals.
Resistance of panicle and leaf hydrangea varieties to disease
Most often, paniculata and large-leaved (macrophylla) hydrangea (hydrangea) suffer from chlorosis, but to a greater extent the latter. This is due to the fact that many hybrid forms were obtained on its basis, which differ not only in a wide variety of colors, but also in weakened immunity.
Resistant varieties
Some varieties of culture, even in the presence of adverse conditions, are resistant to this disease. This is characteristic of varieties that are undemanding to the composition of the soil. True, not all types of this ornamental shrub possess such quality.
Resistant varieties:
- Kyushu;
- Grandiflora;
- Brussels Lace;
- Unique
- Levana;
- Papillon;
- Quadricolor;
- Bailmer;
- Blushing Bride;
- Hanabi
Disease-prone varieties
Not all hydrangeas can boast increased resistance to chlorosis. Some of them, even with minor errors in care, may be affected by this disease.
The following varieties exhibit an increased tendency to chlorosis:
- Bobo;
- Wim's Red;
- Diamant Rouge;
- Pink Diamond
- Blueberry Cheesecake;
- Nikko Blue;
- Lemmenhof;
- Tricolor;
- Gerda Steiniger;
- Cotton Candy.
Important! When choosing less resistant varieties for chlorosis, it is necessary to pay increased attention to prevention.
Methods of treating hydrangeas from chlorosis
Treatment of chlorosis in hydrangea can occur in many ways. In some cases, it is enough to simply feed the bush, and sometimes you should resort to drastic measures. The main thing is that iron for hydrangea becomes available and plant roots can fully absorb it.
When buying new hydrangea seedlings, carefully inspect the leaves
Bush transplant
This method of treatment is used if the soil has lost its air and moisture permeability. This is usually observed if indoor hydrangea is not transplanted for a very long time. In this case, it is necessary to completely replace the substrate in the pot. To do this, you should purchase special soil in the store marked "For hydrangeas."
This method of treatment is also suitable for garden hydrangea if the plant was planted in a soil rich in lime and organic matter. In this case, it is necessary to transplant the plant into well-drained soil.
Important! Water should not stagnate in the selected hydrangea growing area.
Rusty Nails and Tins
This method is considered the most affordable, but it is very effective if you need to urgently help the plant. For treatment, it is necessary to bury rusty nails in the soil near the shrub. They can also be used for indoor hydrangeas.
To accelerate the flow of iron to the roots of the plant, you can clean the rust from old tins and patch it into the soil.
Ready-made preparations
You can cure the flower with the help of professional preparations that are sold in specialized stores. Their advantage is that they contain chelated iron, which improves its digestibility by the plant. Therefore, they give a quick result.
Iron chelate for hydrangeas is part of the following drugs:
- Ferrilen
- Micro-Fe;
- Ferovit;
- "Antichloro".
These professional products can be used to water and spray leaves. But the latter method is more effective, since iron enters the plant tissue within 24 hours after treatment. And when watering, this happens only for 3 days.
"Ferrilen" is effective against hydrangea chlorosis
In the absence of finished products, you can use iron sulfate for hydrangea, which also contains the necessary component. But in order to convert it into a chelate form, certain actions should be carried out.
For preparation, you will need to add citric acid (0.5 tsp) and iron sulfate (2.5 g) to the standing water (1 l). Mix all components and insist for 1 hour.
You can also use another recipe. In this case, you will need to dissolve 10 g of iron sulfate and 20 g of ascorbic acid in 1 liter of water. Mix all ingredients until smooth. After that, you can use iron sulfate in this form for hydrangeas in the garden, suffering from chlorosis.
Important! The shelf life of a homemade solution of iron chelate is 2 weeks, so it is not recommended to procure it for future use.
Preparation of iron chelate based on copper sulfate
When chlorosis develops, it is not always possible to purchase suitable drugs for its treatment. But if necessary, iron chelate can also be prepared on the basis of copper sulfate.
To do this, you will need to dilute the drug according to the dosage indicated in the instructions. In this case, a solution of a saturated blue tint should be obtained. After that, immerse iron objects in it. Periodically, the liquid should be mixed.
After 2-3 hours, the solution acquires a green bottle shade, which confirms its conversion to iron chelate. The resulting product can be sprayed or watered.
Disease prevention
In order not to subsequently treat chlorosis, it is recommended to follow simple preventive measures. This is especially true to prevent the viral form of the disease, since unlike the physiological form, it is impossible to cure it.
Prevention reduces the likelihood of chlorosis in hydrangea
First of all, hydrangeas, especially indoor ones, can provoke chlorosis by irrigation with hard water. To avoid this, it is recommended to add a couple of grains of citric acid per 1 liter to the liquid. You need to do this with every watering.
Other preventative measures:
- Promptly treat plants from pests that can be carriers of viral chlorosis.
- Do not plant shrubs in areas with stagnant moisture.
- Regularly loosen the soil in the root circle and remove weeds that will pick up moisture and nutrients from the soil.
- Regularly feed hydrangea at least 3 times per season, giving preference to phosphorus-potassium fertilizers.
- In hot periods, mulch the topsoil to prevent excessive evaporation.
- Monitor acidity.
- Observe a distance between seedlings of 1.0-1.5 m when group planting.
Hydrangea is a beautiful flower that can decorate not only a personal plot, but also the interior of the house. But for the bush to fully develop and delight with its spherical or panicled inflorescences, it is necessary to provide favorable conditions for it. Otherwise, the plant will sooner or later become ill with chlorosis.