An apple tree leaves curl: possible causes and treatment
Experienced gardeners claim that the state of the plant can be almost accurately determined by the appearance of the foliage. Today we will try to figure out why the leaves of the apple tree curl, consider the main reasons for this phenomenon and methods for solving the problem.
The main causes of leaf deformation on an apple tree
There can be several reasons for curling the leaves of an apple tree:
- insufficient amount of moisture and nutrients;
- damage by pests;
- diseases of fungal infections;
- exposure to low temperatures.
Below we will consider each reason in more detail.
Lack of trace elements
Deformed leaves are one of the signs of a mineral deficiency in the soil. With a lack of calcium, the leaves of young shoots of the apple tree discolor, curl and fall off. The problem is solved by the application of fertilizers based on calcium sulfate, but only under the condition of normal soil acidity... If this indicator is increased, measures should be taken to bring the Ph level to the normalized indicators 5.1 - 7.5.
With a boron deficiency in the apple tree, the leaves turn yellow and fold, and dead areas appear along the edges. To compensate for the lack of boron, it is necessary to treat the tree with an aqueous solution of boric acid: 15 grams / 10 liters of water.
The lack of magnesium is determined by the state of the old foliage of the apple tree. If they turn yellow and curl inward, you should feed the tree with potassium magnesium, magnesium sulfate or add dolomite flour to the soil at the rate of 30 grams / 1 m2 soil.
With a deficiency of phosphorus in the spring, the apple tree does not bloom leaves and young shoots do not germinate. Lack of this trace element during the growing season leads to yellowing and curling of foliage, premature fall of color and fruits. This problem is solved by foliar feeding of the apple tree with a 3% solution of superphosphate.
Insect damage
The folding of leaves in an apple tree often indicates the defeat of the plant by sucking and gnawing insects, among which it is fashionable to highlight:
- common and red-gall aphids;
- leaf roll (apple moth).
The defeat of common aphids can be determined by a strong deformation of leaves and young shoots.
You can notice the red-gall aphids by the reddish galls (swellings). The leaves on the apple tree turn red and curl.
You can determine the defeat of a tree with a leaf roll by the leaves rolled into a tube, covered with cobwebs.
You can fight insect pests using insecticide treatments (Fufanon, Fitoverm, etc.), installing trapping belts, and removing the affected areas of the apple tree.
In the process of vital activity, aphids release a sweetish liquid (honeydew), which serves as a breeding ground for various fungi.
If, in addition to aphids, a black bloom has appeared on the leaves of the apple tree, then this indicates a tree infection with a fungal infection.
Fungal infections
Leaves curl on the apple tree: what to do if fertilizing with mineral fertilizers and the necessary insecticide treatments did not give positive results?
Infectious diseases often lead to the folding of apple leaves, among which the most common are:
- powdery mildew;
- scab;
- bacterial "burn".
Powdery mildew lesions are characterized by the appearance of a gray bloom on the front side of the leaves and their curling "boat". The consequence of the disease is yellowing and premature fall of foliage, the appearance of fungal plaque on the peduncles and fruits.
It is quite simple to determine the damage to the apple tree by scab: the leaves are covered with dark spots. With the development of the disease, the leaf plates curl and fall off. Fruits infected with apple scab become abundantly covered with brown spots, lose their presentation and taste.
With a bacterial burn, all parts of the apple tree are covered with black spots, which resemble areas burned by a fire. This striking similarity gave the name of the disease - burn. Affected leaves curl up and, together with dried fruits, remain on the tree.
The disease is infectious and quickly spreads to all fruit trees and shrubs. Can easily destroy all plants in the garden.
Fungicides are used to treat apple trees for fungal infections. For powdery mildew, the most effective remedies are: Topaz, Topsin, Fitosporin. In case of severe infection, drugs based on penconazole are used.
For the prevention and treatment of apple trees from scab, spraying with a solution of "Bordeaux mixture" is used. As substitutes, drugs perfectly cope with the disease: Abiga-Peak, Hom, Oxyhom.
Antibiotics are used to treat a fire blight. Streptomycin is the most effective against disease.
Why do apple leaves curl in spring
Often, in late April and early May, frosts occur in the Russian Federation, which lead to blackening and deformation of young leaves on fruit trees. On the contrary, this period is also characterized by the increasing activity of the sun, which can lead to sunburn.
When exposed to low temperatures, the cell membrane of the leaves is ruptured, which leads to their drying out and deformation. You can distinguish frostbite of an apple tree from lesions by fungal infections by the color of the wood. To do this, you need to make an incision in the affected area.
Healthy wood is light gray in color. If the damage is weak, the cambium color is light yellow. With severe frostbite, the color of the wood is dark brown. The death of an apple tree area from freezing is characterized by a brown cambium.
This problem is solved by competent pruning of damaged areas. If cracks appear on the trunk (frostbites), then they should be filled with wood "glue", and then treated with the damaged area with "Ranet". The main remedy for sunburn is timely whitewashing an apple tree.