Why do the leaves of a Chinese rose or hibiscus disease turn yellow

The Chinese rose, or hibiscus, is a rather popular plant among flower growers. As the name suggests, China is the birthplace of culture. Despite the fact that it is quite simple to care for a flower, it can get sick from time to time, its leaves acquire a yellow tint, plaque appears on them, or they begin to fall off. To find out how to cope with these problems, you need to get more information about hibiscus diseases and the factors that cause them.

Causes of diseases

If you systematically violate the rules for keeping a flower, problems with it cannot be avoided. The main causes of the disease of an ornamental plant can be:

• keeping a pot with a Chinese rose in a room with too dry or too humid air;
• neglect of spraying the crown in hot weather;
• planting a plant in open ground in an area with direct sunlight or blown by the winds;
• the presence of pests;
• long-term cultivation of hibiscus without transplanting;
• placing the plant in an unnecessarily shaded place;
• watering with water containing harmful impurities;
• lack of fertilizing, etc.

Hibiscus is a very beautiful flower, which is easy to care for.

Hibiscus diseases, their treatment

White bloom on the leaves

White bloom on hibiscus foliage is the main symptom of such an unpleasant disease as powdery mildew. It spreads very quickly, after a short time, almost every leaf of a Chinese rose appears in white specks. The spots gradually increase in size, become brown and acquire a filmy structure. The leaves begin to curl, wither and fall off. If you do not take any measures, the indoor flower will die very quickly.

If the disease was detected at the initial stage, the flower can be saved. The first step is to remove all leaves affected by powdery mildew. The plant must be treated with a solution of antibiotics. In their absence, it is allowed to use some home remedies.

The most commonly used solution is baking soda (two tablespoons per liter of water). The composition should be thoroughly sprayed on the entire plant.

Another common option is a soap solution with the addition of copper sulfate. Having coped with plaque on the leaves, you should provide the hibiscus with the most comfortable conditions for growth in order to avoid a recurrence of the problem.

Dropping unblown buds

Some growers complain that hibiscus begins to shed unblown buds. Most often, the reason why the plant does not want to bloom, and its unopened bud falls off, is due to the fact that the care of the Chinese rose is not organized correctly.

If a hibiscus drops its buds, there is reason to start worrying.

The following factors can cause the problem:

• too low or high temperature - so that the plant does not begin to shed its buds and can bloom normally, it should grow at +23 degrees in summer and +18 degrees in winter;
• direct exposure to sunlight - they burn the plant, and the still unblown bud begins to dry out;
• too frequent watering, causing rotting of the root system;
• poor drainage;
• lack of feeding - lack of nutrients in the soil is stressful for the Chinese rose;
• frequent plant movements - the response of the hibiscus to stress is the dropping of buds.

Hibiscus chlorosis

Many novice growers are wondering when hibiscus leaves turn yellow and fall off what to do. If no pest has been identified, and there is no cobweb or plaque on the foliage, most likely this is a fairly common disease. The answer to the question of why the leaves of hibiscus turn yellow lies in such a diagnosis as chlorosis.

Hibiscus chlorosis is a fairly common disease

This disease is associated with a violation of the formation of chlorophyll in the foliage. At the same time, the yellowish leaf has green streaks.

The reasons why chlorosis can develop and the leaves turn yellow are as follows:

• lack in the soil of elements such as magnesium, zinc, sulfur, lime and iron;
• insect-borne infection or microorganisms;
• germination defects;
• poor soil condition;
• lack of drainage;
• hereditary factor.

Not only yellowing of the leaf plate is a symptom of chlorosis. In addition, the leaves begin to decrease in size, their edges begin to curl, the shape of the buds and flowers changes, and the apical shoots dry out.

Chlorosis treatment is possible only with the use of special preparations: Agricola, Fkerovit, Antichlorosin, Iron Chelate, etc. The compositions are applied at the root or used for spraying.

To prevent yellowing of the foliage from starting, some preventive measures will be effective. In particular, it is important to choose a good substrate for the flower - light and permeable, pay attention to the acidity of the soil and prevent it from alkalizing, and periodically water the plant with acidified citric acid water. A few grains are enough per liter of water.

In most cases, if you organize the right care, the questions why the leaves of the Chinese rose turn yellow and fall and what to do in this case, most likely, will not arise.

Hibiscus pests

Another condition why the leaves of the Chinese rose turn yellow is an attack of pests.

Aphids on hibiscus

The appearance of a pest such as aphids on hibiscus is not an uncommon occurrence. When this parasite appears, not one branch is usually affected, but the entire plant as a whole. If you do not worry about solving the problem in a timely manner, foliage may fall off, the plant itself will eventually die.

Aphids often attack hibiscus

Young and succulent shoots are especially attracted to insects. You can understand that the Chinese rose is infected with aphids by the deformation of the leaf plates and the presence of a large number of sticky secretions.

The fight against aphids should begin with the mechanical removal of insects from the flower. This is done with soap and an ordinary cotton swab. You should not dwell on this - after the physical removal of aphids from the leaves and stems, it is imperative to use chemical preparations like Biotlin, Aktara, Anabazin, Nicotine sulfate and some others.

It is unlikely that it will be possible to cope with the pest from the first call. So, most likely, the processing will need to be repeated. Usually, the plant is re-sprayed a couple of weeks after the first.

On the Internet, you can find many folk methods for combating aphids, but all of them are not very effective when it comes to serious damage to the culture.

Scabbard on hibiscus

The shield can cause very significant damage to the Chinese rose. We are talking about a small pest, the length of which is no more than 5 mm. Their color can range from light to dark brown.

The scale insect can cause great harm to the Chinese rose

Since scale insects live mainly in colonies, they are able to inflict very significant damage on hibiscus.When summer begins, it is highly recommended to periodically inspect the plant pot for the presence of harmful insects.

The scale insects suck out all the nutrients from the flower that are vital for its growth. When damaged by insects, growths and curvatures appear on the trunk, the shoots begin to dry out, and the leaves turn yellow and fall off over time.

You can fight pests using both traditional and chemical methods. Of the materials at hand, alcohol, onion infusion, decoction of tobacco leaves and garlic infusion are especially effective. As for chemistry, any insecticide should be used to combat scale insects. For example, Karbofos, Fitoferm, Aktellik and some others.

Black aphid

Another parasite that can cause significant harm to the Chinese rose is the black aphid. This insect is very similar to the common aphid, but it is (as the name suggests) black. Usually this insect infects plants growing in open ground. The parasite has wings, lives in large colonies and infects a flower quickly and unexpectedly. At the first symptoms of the appearance of a black aphid, a comprehensive fight against the parasite should be started. At the same time, it is recommended to simultaneously apply mechanical, agrochemical and folk methods of struggle.

Mechanical methods include applying glue gels and sticky tapes to hibiscus branches, watering under high pressure of water and physically crushing insects. From agrochemicals, insecticides such as Dichlorvos, Kortlis, Commander, etc. can be used.

Folk recipes for dealing with black aphids suggest spraying infected plants with a weak Ferry solution or garlic infusion, pollination with pure ash, smoke bombs for fumigating the site, and much more.

So that the hibiscus does not get sick and does not suffer from parasites, you should pay maximum attention to the flower and respond to any changes in its normal growth, leaf formation and flowering.

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