Why do blackcurrant leaves turn yellow. Useful properties of currant leaves

Black currant- it's unpretentious berry bush, but when growing it, gardeners sometimes face some problems. One of them is the yellowing of the leaves. The leaves may turn yellow gradually throughout the summer, or they may change color rapidly, and then begin to fall off.

chapter 1. Causes of yellowing currant leaves

There are many factors for yellowing foliage, and the sooner the cause is determined, the easier it will be to eliminate it.

Section 1. Pests

One of the reasons for the change in the color of the foliage is the attack of pests such as gall aphids, currant glass or spider mites. It is not difficult to identify them if you carefully examine the entire plant, because insects leave other traces.

gall aphid, or in another way - hairy aphids, feed on leaf juices, which causes their deformation. Surface sheet plate swells, forming tubercles, which can be either yellow or red.

Most often, young leaves on the tops of the shoots are damaged, which slows down the growth of the plant and worsens the yield in the next season. Aphids lay their eggs under the bark, and they overwinter there until the next year.

currant glass jar is dangerous in that it lays eggs inside shoots that have even the slightest cracks. Caterpillar larvae emerge from the eggs, which feed on the inside of the shoots, leaving voids in them. They move down, and spend the winter in that part of the branches, which is located closer to the ground.

The final growth of the larva is 2 cm. For the entire period of being inside the shoot, the glass larvae gnaw out its entire core, which disrupts sap flow and the process of photosynthesis. The leaves turn yellow and fall off after a while.

spider mite attacks currants most often in hot, dry weather. It can be seen if you look at the bottom of the sheet. It is strewn with very small black spider insects. At the internodes, at the junction of the leaf petiole with the shoot, a thin cobweb is noticeable.

The spider mite sucks the juice from the foliage, piercing it. The outer surface is first covered with small yellow dots, which quickly merge and the leaf appears completely yellow. After a while, it dries up and curls up.

Section 2. Nutrient deficiency

Currant leaves can become yellow due to a lack of nutrients:

with a lack of nitrogen, the foliage turns yellow gradually, and first the color of the veins changes, and then the tissue between them. Leaves fall only if the soil is very depleted. Confirmation that the currant lacks nitrogen is also the fact that the shoots are strongly stretched and become thin;
with a lack of potassium, only the edge of the leaf turns yellow, and the leaf itself does not change color;
if there is little iron in the soil, then the leaves become pale green and remain so long time. They turn yellow much later, while their turgor does not change;
if the plant lacks magnesium, then only the lower leaves turn yellow, while the surface between the veins changes color, and the veins themselves remain green.

Section 3. soil moisture disturbance

The color of currant leaves can also change if watering is disturbed. This occurs both when the soil is dried out in the near-stem circle, and when waterlogged. If watering is insufficient, then small roots, which are responsible for the absorption of moisture, partially die off. With constantly moist soil during the rainy season, the roots rot. At the same time, the plant does not receive a sufficient amount of trace elements, which changes its appearance.

chapter 2. What to do if currant leaves turn yellow

If the cause of the change in the color of the foliage is identified, then it will not be difficult to eliminate it. It is important to carry out all activities as soon as the first changes appear.

Section 1. Top dressing

If there is a shortage of nitrogen, its supply can be replenished with the help of organic fertilizers - compost or rotted manure. You can replace them with urea.

If the currant does not have enough potassium, then potassium sulfate, potassium chloride or potassium magnesia are added. These fertilizers dissolve well in water, and liquid dressings are quickly absorbed.

Iron is replenished with iron sulfates or chelates. It should be remembered that iron sulfates are applied to the soil, and chelates are used for foliar top dressing. This is due to the fact that in this way iron is absorbed completely.

With a lack of magnesium, currants are fertilized with potassium magnesia, magnesium sulfate or dolomite flour. A large number of magnesium is found in wood ash.

Section 2. Processing with chemicals

When applying chemicals to control pests on currants, it is important to remember that spraying with some agents should be done 30 days before harvest or any time after all the berries are harvested.

Against gall aphids and spider mites apply:

"Agravertin" - pests stop eating plant sap 6 hours after treatment, and their complete death occurs after 3-4 days;
"Aktofit" - the complete death of pests occurs after 3 days. Apply at a temperature not lower than +18°C. Berries can be eaten two days after spraying;
"Fufanon" - begins to act in a day, currants are processed 20 days before the berries ripen.

It is more difficult to deal with currant glass, because the larvae are protected by the bark of the shoots. Spraying is effective during the period when butterflies begin to fly.

They use drugs such as Karbofos, Fitoverm, Agravertin. If the moment is missed, then the shoots in which the butterflies have already managed to lay their eggs are removed. You can recognize them by damage on the bark, because females choose only damaged branches for laying eggs.

Section 3. Folk remedies to combat yellowing currant leaves

From gall aphids and spider mites, an infusion of tobacco or red pepper in pods is used. Prepare them as follows:

500 grams of tobacco is poured warm water(10 liters) and insist for a day. Then filter and add a little green soap;
a concentrate is prepared from red capsicum - 1 kg of pods is poured with water (10 liters) and boiled over low heat for 1 hour. After cooling, strain and pour into small containers. For processing, add 150 grams of concentrate to a bucket of water.

To scare away the glass case, the currant bush is sprinkled with dry mustard, wood ash or tobacco dust. After rain, the procedure will have to be repeated. The soil in the trunk circle is loosened, weeds are removed and the same means are poured. In order to prevent egg laying, all damage to the bark must be covered with garden pitch.

Chapter 3 Prevention

Only with regular care, currant leaves will not turn yellow either from pests or from a lack of trace elements. Preventive measures should begin in May:

the soil in the trunk circle is carefully loosened and fertilizers are applied. In the spring, currants need complex top dressing - nitrogen, phosphorus and potassium;
all weeds growing nearby must be removed;
damaged branches are cut and burned. If voids are visible on the cut, then the shoots are cut to solid wood;
if the spring is dry, then regular watering is necessary at the rate of 2 buckets per 1 adult bush.

In June, you need to carefully examine the plant. If pests are noticed, then the damaged foliage is removed. In this period folk remedies, used for pest control, can be used as a preventive measure.

In July, until the crop is harvested, it is not recommended to use any means for spraying blackcurrants. They carry out such preventive measures as loosening the soil and applying complex dressings, which include phosphorus and potassium.

With proper care, such a problem as yellowing of leaves in currants is rare.

Chapter 4. Video

Blackcurrant is a plant that is resistant to diseases and unpretentious in care. But there are times when it gets sick. Yellowing of the leaves is considered the most common ailment of blackcurrant bushes. There may be several reasons for this phenomenon. Let's consider them in more detail.

Harmful insects are the main reason why leaves turn yellow

Gall aphid is enemy number one for currant bushes. This type of aphid reproduces very quickly: several generations are born in one season. The pest feeds on the sap of the plant, which it sucks from the leaves. Bubbles of a yellow or brown hue appear on the areas affected by aphids, then the entire leaf turns yellow and falls off. The gall aphid very quickly colonizes the entire bush, therefore, at the first signs of its appearance, it is necessary to treat the plant with special preparations.

Currant glass is another pest of shrubs. Caterpillars gnaw through young shoots, suck out the juice, which is the reason for the yellowing of the foliage and the general wilting of the plant. Regular inspection and timely spraying of bushes for the destruction of harmful insects will prevent the appearance and reproduction of the glass case.

Blackcurrant? Reason #2

Adverse weather can also affect the development and growth of the bush. The reason for the premature yellowing of the foliage on the currant may be drought. In very hot summer days the plant needs to be well watered, and the soil around the bush should be regularly loosened so that the healing moisture does not evaporate very quickly.

High humidity can also cause blackcurrant leaves to turn yellow. Abundant and frequent watering, prolonged rains adversely affect the life of the shrub. The water washes out nutrients from the soil, and the plant does not receive the elements necessary for the full development.

An incorrectly chosen landing site is the reason why blackcurrant leaves turn yellow

Bushes in the garden should be located at a distance of 1 meter from any other crops, otherwise the plant will be limited in access to light and space. The leaves on such a shrub will turn yellow and crumble. Berries in such conditions are tied small, they are sour in taste.

Currant leaves turn yellow even when the bush grows either in sandy or in hard, nutrient-poor soil. In this case, the plant needs to be transplanted to a more appropriate place or regularly apply mineral and organic fertilizers to the soil.

Can top dressing be the reason why blackcurrant leaves turn yellow?

When fertilizing bushes, you need to adhere to the rules and regulations for their application. Excess peat in the soil is striking root system plants, which provokes yellowing and falling leaves. Young currant bushes are very sensitive to potash and phosphate fertilizers. An overdose of them causes a root burn, blanching and shedding of foliage and ovaries.

In order for the plant to fully develop, preventive examination of shrubs, a favorable environment for their growth and development, and timely treatment of plants and soil are necessary. Provide currants in your garden with such conditions, and it will delight you with a healthy look and a rich harvest.

Healthy and well-groomed currants are rarely affected by harmful microorganisms and insects, since they have stable immunity. Currant, like others fruit crops becomes weakened and vulnerable to pests and diseases as a result of improper care, excessive or insufficient fertilization, non-compliance with agricultural practices and mechanical damage. In the article we will tell you why the leaves of the currant turn yellow and dry in spring and summer, we will give an analysis of the reasons.

Currants with low immunity in the vast majority of cases become infected with viral or fungal diseases.

Consider the most common causes, causing premature yellowing, drying out and falling of leaves in currants. Consider effective ways pest and fungal disease control, and effective ways protection of currants from non-infectious diseases caused by a violation of the water, light, nutritional regime and adverse weather and soil conditions.

Currant diseases leading to yellowing, drying out and premature leaf fall

Fungal and viral diseases currants affect mainly leaves and petioles. The first signs of infection with pathogenic spores are observed in early spring. In the absence of timely treatment, fungal diseases can destroy the plant in one season. Consider several types of currant diseases that cause yellowing and drying of the leaves in spring and summer:

Anthracnose appears as brown dots on the surface of the leaf blade. In the affected areas, it destroys chlorophyll, which leads to discoloration of the leaf blade. Over time, brown dots grow and begin to merge into a single spot. The spots increase in size, which leads to premature drying and leaf fall.

Anthracnose disease is activated during the rainy season and during high humidity air. Disease spores spread harmful insects and transported with water.

Affected red currant leaves fall off at the initial stage of anthracnose infection.

columnar rust - This fungal disease, which is spread by insect pests or with a wind stream from such coniferous trees like cedar or weymouth pine. The first symptoms of the disease are the formation of yellow spots on outside sheet plastic. On the lower part, yellow growths in the form of hairs form.

Columnar rust simultaneously affects the upper and lower parts of the currant leaf.

Septoria appears on the leaves of currant in the form of brown spots. As the disease develops, the spots lighten, only the brown edging of the spot remains intact. With a strong lesion, premature fall of currant leaves is observed. Infection occurs by spores that overwinter in fallen leaves.

The vein mosaic on the currant is not treatable. Infected currant bushes must be destroyed.

With a disease of septoria, brown spots appear not only on the leaves, but also on the fruits of the currant. Septoria often develops on the leaves and fruits of blackcurrant.

vein mosaic – viral disease is activated after the leaves bloom. Attacks leaf veins. It appears as a bright yellow pattern on currant leaves. Over time, the leaves dry up and fall off.

The sources of vein mosaic disease are in 90% of cases insect pests such as aphids and mites. In 10% of cases, the source is contaminated inoculum.

In the table, consider chemicals and optimal time for the treatment of infected currant bushes with fungal diseases:

Types of fungal diseases	Chemicals	Treatment
Anthracnose	Nitrofen	Before bud break
	Cuprozan	Before flowering
	Colloidal sulfur 1%	1. After flowering. 2. After harvest
columnar rust	Bordeaux liquid 1%	1. During the period of leaf blooming. 2. During the budding period. 3. After flowering.
Septoria	Nitrofen or Hom	Before bud break
Septoria	Bordeaux liquid 1%	1. Before flowering. 2. After flowering 3. After harvest
vein mosaic	Not amenable to treatment. Destruction of the infected currant bush is required.

Tip #1 When treating affected currant bushes with fungal diseases, Bordeaux liquid can be replaced with a solution of copper oxychloride. Copper chloride has a strong bactericidal effect. To avoid the accumulation of toxic substances in currant berries, processing should be stopped 20-25 days before harvest.

Currant pests causing premature yellowing and leaf fall

Premature yellowing and falling of the leaves of the currant occurs as a result of the attack of insect pests. These pests include:

gall aphid;
currant glass;
spider mite.

gall aphid very voracious and prolific insect. Inhabits currants in spring. It feeds on plant sap until mid-summer. Continuous absorption of juice leads to the exhaustion of the plant. In places of damage, growths appear.

Gall aphid infects white and red currants. In rare cases, it is found on blackcurrant.

currant glass jar looks like a wasp. Inhabit currants after flowering. Forms oviposition under the bark of shoots, from which voracious caterpillars appear. Caterpillars eat away the core of the shoots. caterpillars eating soft tissues shoots, form passages up to 60 cm deep, in which they remain to winter until spring. In the spring, caterpillars gnaw their way out to the surface of the shoot, pupate and turn into butterflies.

The currant glass case affects all types and varieties of currants. The glass case damages up to 50% of blackcurrant shoots and up to 30% of red and white currants.

Tip #2 You can scare away the currant glass folk way. During the period of mass summer, treat currant bushes with strong infusions from plants such as wormwood and tansy. The pungent smell of herbal infusions disorientates and repels glass-case butterflies.

spider mite hides in the scales of the kidneys, so it is quite difficult to see the pest with your own eyes. The main sign that a spider mite has wound up on a currant is swollen and deformed kidneys. Inside each swollen currant bud, several generations of mites can live simultaneously. Leave the monastery as soon as it becomes crowded. In search of a new home, they move to healthy fruit-bearing shoots.

Ticks move to healthy branches during the budding period. This period is considered the most favorable for the treatment of currant bushes with pesticide preparations.

In the table, we consider preparations that will help destroy gall aphids, glass cases and spider mite on currant:

Currant pests	Preparations	Drug consumption	Favorable period for processing
gall aphid	Nitrafen 3%	0.5 l per 1 bush.	5-6 days before bud break and after leaf fall.
Glassware	Nemabakt or Antonem -F	250 ml per bush	At the stage of bud break
spider mite	Oberon, Aktelik, Nitrafen	200 ml per bush	At the budding stage

Yellowing of currant leaves as a result of a violation of mineral nutrition

Yellowing of the leaves of the currant is observed with a deficiency and excess of nutrients. In the table, we consider how the excess and shortage of any nutrient affects the state of the plant:

Batteries	The state of the plant with an excess of nutrients	The state of the plant with a lack of nutrients
	The vegetative mass is intensively growing. The leaves are large, bright green. The leaves are fragile.	The leaf blade is discolored. Green color retain only the veins. Leaves fall prematurely.
	The petioles and the lower part of the leaves acquire a reddish tint.	Small spots of cranium or purple hue. The edges of the leaves curl down. Leaves fall prematurely.
Potassium	Leaves curl down. Affected leaves do not die off, but do not fall off until the end of the growing season.	The edges of the leaves darken, dry out and fall off. Only the core of the sheet remains intact.
Calcium	The growth and development of the plant is suspended. Leaves turn yellow in patches.	The upper part of the leaves acquire a purple hue. The lower part of the leaf becomes discolored and dries out.
Iron	The leaves turn yellow mainly between the veins. The leaves look sluggish.	The leaf blade turns yellow completely. The edges of the leaves dry out and fall off.
Bor		Only the main veins on the leaf blade turn yellow. Drying and shedding of the tips of the leaves is observed.
Manganese	Does not affect the condition of leaves and shoots.	Dry gray plaques form on the leaves.

Experienced gardeners recommend feeding currants several times during the season. Nitrogen fertilizers must be applied in early spring. An effective nitrogen fertilizer for currants is urea. Urea is best applied in liquid form. To prepare the solution, 1 tbsp is enough. urea per 10 liters of water. Solution consumption - 10 liters of water per bush.

In summer, currants should be fed organic fertilizers. It is enough to prepare a solution of mullein in a ratio of 1 to 10. The consumption of the solution is 1 bucket per bush. In autumn, currants are best fed with a nutrient mixture of compost, superphosphate and potassium sulfate. The mixture is prepared at the rate of 5 kg of compost, 3 tablespoons of superphosphate and 2 tablespoons. potassium sulfate.

Common gardener mistakes leading to yellowing of currant leaves

Carry out the wrong feeding mineral fertilizers. Deficiency and excess of basic nutrients leads to yellowing of the leaves.
Produce rare watering. So with a lack of water, young currant roots die off. The plant stops getting useful material, castings begin to turn yellow and fade. Due to the lack of nutrients, the currant begins to shed its foliage in order to survive.
Excess water in the near-stem circles leads to decay of small roots. The plant stops receiving nutrients, which leads to yellowing of the leaves and weakening of the plant as a whole.

Frequently Asked Questions for Gardeners

Question number 1. How to detect a currant glass case?

The glass is hard to find. The glasswort lays its eggs under the bark of the shoots. The caterpillars that have appeared live in the core of the shoots for up to two years, feeding on the juice of the plant. In this regard, several currant shoots should be cut, on which there are yellowed leaves. If there are black dots in the core, most likely the currant is affected by a glass case.

Question number 2. What plants are intermediates for gall aphids?

In the second half of summer, the gall aphid inhabits such plants as oregano, chistets, lavender, mint, sage and thyme. When fighting gall aphids on currants, the above plants must be destroyed.

Question number 3. What plants should be planted between the rows of currants to scare away pests?

You can scare away currant pests if you plant marigolds, garlic and calendula nearby.

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