Magnolias are ornamental shrubs to trees, which are gaining more and more popularity among growers of ornamental plants. In favor of magnolias , their beauty speaks at the time of flowering, when they are sprinkled with a plethora of flowers in bright shades of red, pink, yellow and white.
At this time - early spring - most ornamental trees still do not bloom. They also attract attention with their typical sweet scent. After flowering, their beautiful large leaves stand out and after the end of the growing season there are interesting fruits on them.
Although magnolia is a hardy and not very demanding tree, it still avoids diseases and pests .
Now about some magnolia diseases
Anthracnose of magnolias
In this disease, black spots, up to 3 mm in size, appear on both sides of the leaves. They can also form spots in bronze-brown or red with a colored border - this indicates that the plant is infested with fungi Botrytis cinerea , Cercospora handelii or Pestalotia spp . The disease attacks plants that are planted in a cool and humid place. This disease can be prevented by good drainage, ensuring air flow and early removal of damaged parts of the plant. Irrigation, which moistens the leaves, should be avoided, as the moisture present can cause anthracnose . If this disease is detected, it is necessary to perform a protective chemical spray with some product for leaf staining. The spray should be repeated after 14 days as needed - 2-3 times.
This disease is caused by the fungi Verticillium dahliae and Verticillium albotrum . The disease is accompanied by wilting of the leaves , which initially turn yellow, the edges are brown and the leaves look tanned. Gradually, brown spots also appear on the branches. Typical for this disease is the black color of the roots . In this disease, the shrub or tree may wither completely. The infection is transmitted by water for irrigation, infected parts of plants, soil, tools. This disease can be prevented by ensuring that there is no mechanical damage to the roots. The large amount of soil will not be changed at once, and especially the infected plants will be removed in good time. Chemical protection with fungicides is not effective. In case of recurrent disease, it is necessary to move to the cultivation of Magnolia species more suitable for the site.
Green spotting of leaves
Green spotting of the leaves is another disease that can affect Magnolia . It is caused by the algal algae Cephaleuros virescens . These algae cause diseases to plants with leathery leaves, including magnolias. We find out that the plant is infested with this disease, based on the fact that the leaves form spots of orange, brown, gray or even green with a diameter of about 5 mm. The leaves are mainly affected, but the infection can also manifest itself on twigs, which are stunted and lesions form on them. The infection is spread by rainwater and thrives most in a humid warm environment. Good soil drainage and proper airflow act as protection against the disease. Copper -based sprays are used for chemical protection .
It is a physiological jaundice, it is a disease of the whole plant. The leaves turn yellow-green to yellow. Sometimes the veins of the leaves remain green and the rest of them turn yellow. Calcium is a common chlorosis in Magnolias. Calciosis usually manifests itself in hot summers, but spring has been rainy. This disease causes an excess of calcium in the soil. Calcium causes an increased alkaline reaction, which prevents the plant from absorbing iron in sufficient quantities. Iron needs a plant for photosynthesis . Unsuitable calcium soils can be treated by adding ammonium sulphate to the fertilizer, a large amount of peat or small doses of powdered sulfur . Watering plants with a solution containing organic iron compounds - lignohumates - helps faster. Previously, the introduction of a solution of ferrous sulfate ( green scale) to the root system was used. Quick help can also be provided to the tree by spraying with the content of rapidly absorbable iron.
Magnolia powdery mildew
The disease is manifested by a white floury coating, especially of young leaves. The leaves turn brown and begin to fall off. It is necessary to use a good fungicidal spray to treat the infested tree. We repeat it 2 to 3 times in a time interval of 7 - 10 days. Plants suffer from powdery mildew , which are planted in unsuitable habitats where it is too hot. Another reason is the weak air flow in the crown. More suitable than treating a diseased plant is suitable prevention. It is necessary to prevent the spread of spores, which can be ensured by keeping the plant environment clean - without weeds, fallen leaves and plant residues. Better air circulation can be ensured by removing excess branches.
Spotting of magnolia leaves
Cladosporium, Pseudomonas syringae and Septoria can cause another Magnolia disease , namely Magnolia leaf spot. The onset of this disease is manifested by small black or purple spots. As the disease progresses, the spots gradually enlarge, with the spots having a white center and a dark purple margin. For chemical protection, it is suitable and effective to use one of the sprays against leaf spot. Spraying should be started immediately after signs of disease. The spray must be repeated 2 to 3 times, still after two weeks. Since this disease occurs mainly in wet gardens , where the conditions are best for its origin and development, proper irrigation is a suitable protection. Timely removal of disease-infected leaves is also very important. It is also necessary to ensure good air circulation in the crown by removing excess and tangled branches.
Professional imitation plants
We have described 3 diseases that cause Magnolia a lot of problems. It follows that it is not entirely easy to correctly and timely diagnose the disease. It is not easy to apply the right treatment of a favorite plant to a sufficient extent. This can lead to fatal consequences - death. It might be worth thinking about an alternative that will save us time and energy. It will allow us to have the illusion of a favorite plant even in places where it is not possible to grow it - you need to have an "always green" branch of a flowering Magnolia anywhere in the interior. With the ingestion of essential oil as a fragrance, the illusion is perfect. Investing in professional imitation is advantageous and long-term. Today, they are not derogatory called artificial flowers at all . Thanks to the materials used for production, their longevity is guaranteed whether the "plant" site is the interior or exterior .