Raspberry bushes: description
Raspberry is a semi-shrub with erect stems that reach a height of 1.5-2.5 meters. The root system is powerful and very branched. After planting, raspberries usually begin to bear fruit the next year. However, today, thanks to the efforts of breeders, there are remontant raspberry varieties that bear fruit on the shoots of the first year of life.
Note! The plant is unpretentious, but requires little but constant attention, as well as regular prevention of various diseases. Many cultivars are susceptible to disease, although modern species are highly resistant. Completely immune does not exist.
The main types of diseases that raspberries are exposed to are viral and fungal infections. All drugs that help fight the disease must be used before the berries ripen.
Proper planting and care of raspberries strengthen the plant’s resistance to insects and diseases. Affected raspberry stalks should be cut almost to the root and burned. In the spring, the plantings are well cleaned of the remnants of foliage and debris, and then treated with Bordeaux liquid.
The main diseases of raspberry, and the fight against them
Diseases and enemies of raspberries are diverse, so the gardener should pay special attention to this problem. You need to look at the condition of the leaves, stems and shoots of the bush. Raspberry diseases can not only reduce the yield of berries, but also destroy the entire plantation.
Diseases of fungal origin
Fungal diseases of raspberries are very common. It is the berries that are most affected by fungal infections. Raspberry protection is carried out immediately after the first signs appear.
White and purple spots
White spot is a common fungal disease of raspberries. When the disease affects leaves and stems on which many round spots appear. They are pale brown at first, eventually becoming white in the center, with dark dots. The diseased leaf tissue is destroyed and soon falls off. Purple spotting is distinguished by the purple color of the spots on the shoots and leaves.
Disease control measures:
- thin out plantings;
- treated with drugs containing copper;
- remove affected bushes.
Gray rot (botrytis) affects berries, leaves with shoots. Small gray spots appear on the fruits, which increase. The berry is covered with a gray coating, which contains spores of the fungus, and begins to rot.
Gray rot (botrytis)
Spores can infect all raspberries. Exacerbation of the disease is observed on fairly cool days with high humidity. The disease is spreading very quickly, and action must be taken immediately. Infected plants die.
The density of plantings leads to the spread of gray rot, so plantings are always thinned out. This allows for good ventilation and protects against disease. Do not place plants in lowlands with high humidity.
Anthracnose develops in spring, after the leaves bloom. It appears as single gray-white spots with a purple border on the stem. They then coalesce to form ulcerative lesions. The bark peels off the stems, the leaves curl and dry. The fruits turn gray and also dry up.
The fungus spreads rapidly in damp weather, is resistant to frost, and therefore can overwinter on the stems of infected plants. To prevent the disease, resistant varieties are planted, infected plant residues are destroyed, planting density is observed to ventilate the plantations. After harvest, affected plants are burned and plants with mild signs of infection are cut out.
Phosphorus-potassium fertilizers are applied under the autumn digging of the soil. In the spring, when the buds open, the plants are treated with 15% Bordeaux liquid. The first spraying is carried out when the plants reach a height of 20 centimeters, the second – before flowering, the third – after flowering.
Rust. When the disease affects the stems and leaves of raspberries, yellow growths appear on them. Affected leaves dry up prematurely and fall off, young shoots slow down their growth, and gradually die off. Spores calmly endure the winter on fallen leaves. Therefore, it is necessary to carefully remove the remaining foliage from the areas where raspberries grow, spray with Bordeaux liquid. During the rainy season, the development of the disease continues until late autumn.
Bacterial root cancer can infect those bushes whose roots are damaged. Outgrowths in the form of tubers form on the roots of the plant, shoot growth stops, raspberry leaves turn yellow, and the fruits lose their sweetness.
Bacterial root cancer
This disease is not detected immediately. Raspberries first slow down their growth, and then lose their taste: the fruits become tasteless. You can detect the disease when transplanting bushes. The cause of the disease may be alkaline soil or long-term cultivation of raspberries in one place. Such raspberry diseases are very difficult to treat. The planting site of the bushes is recommended to be changed after 3-5 years.
Viral diseases that raspberries are exposed to
Viral diseases affect the root system, stems, leaves of the bush and lead to the death of the plant. The causative agents of viral diseases penetrate the tissues through cuts and cracks.
Important ! There is no cure for viral diseases. With the help of good care and preventive treatments of bushes from aphids that carry the disease, you should try to protect raspberries from infection. Immediately remove and destroy diseased specimens from the site.
Raspberry chlorosis. Why do raspberries turn yellow? The carriers of the virus are insects: nematodes, mites or aphids, which expose raspberries to such a serious disease as chlorosis. First, the sections of the leaf plate between the veins turn yellow, then the yellowness spreads throughout the leaf. The shoots are stretched, thinner, the fruits become small, deformed and dry quickly. Too wet soil and too high acidity of the soil on the site provoke the development of infection. In addition, the disease can be caused by a deficiency of trace elements (manganese, iron, boron). Another cause of the disease is watering plants with cold water.
Raspberry mycoplasma disease, which is called the shoot, or “witch’s broom” is a complex viral disease. It is almost impossible to cure it. The plant forms sterile small shoots from 30 to 50 cm high to 200 on a bush. If such a specimen appears on the site, it is immediately destroyed until the disease has spread to neighboring bushes.
Raspberry mosaic refers to viral diseases. Viruses are spread through wounds caused by non-sterile instruments, through the bites of sucking insects. The leaves become variegated, with alternating light and dark green areas, asymmetrical in shape.
Fruiting on the affected bushes is reduced, the fruits become tasteless and hard. Young shoots are degenerating. Damaged bushes should be burned.
Curly raspberries . The leaves of diseased plants become smaller, become wrinkled and stiff, and the underside of the leaf plate turns brown. The fruits of diseased bushes are deformed and dry out, and the plant itself dies.
In addition to diseases, this bush is often affected by insects. The most dangerous raspberry beetle and its larvae. They reduce the number of fruits by 50%. The most dangerous period for raspberries is its flowering. At this time, female insects lay eggs, which turn into larvae in June.
To prevent the appearance of a raspberry beetle, the bushes are treated with Confidor, Decis or Spark preparations. In addition, during the pupation period, they dig up the ground around the bushes.
Strawberry-raspberry weevils cause significant damage to the leaves and flowers of the plant. To prevent this from happening, the bush should be sprayed with Confidor or Spark. Karbofos is also considered a fairly effective drug.
Raspberry fruit fly. Pest larvae hibernate under bushes at a depth of 5 cm. After warming up the soil, flies appear. They lay their eggs in the axils of leaves and on the tops of raspberry shoots. Pest larvae feed on the core of the shoots, destroying the stems from the inside. Before the raspberries begin to bloom, they gnaw on the stems. To combat the pest, they dig up the soil in the fall, before flowering, cut and destroy the affected bushes. Sprayed with karbofos from flies.
Leaf aphids are widespread pests of horticultural berry crops. It is very harmful if the raspberry is in a shaded place. Aphids settle in colonies at the ends of the shoots and in raspberry inflorescences, on the underside of the leaves and feed on their juice. As a result of pest damage, the leaves curl, the shoots are bent and grow poorly, the flowers dry out. In addition to damage to the shoots, they are carriers of raspberry viral diseases. More dangerous than aphids in dry years. It is necessary to fight the pest with the help of chemical and home remedies.
The spider mite affects not only raspberries, but also many berry crops. The tick, located on the underside of the leaves and feeding on their juice, braids the leaves with a thin cobweb. Damaged areas become discolored as the disease progresses. The leaves gradually dry out and eventually fall off.
Gall moth on raspberries lay their eggs in cracks and damage the bark in the lower part of the shoots, forming galls – swellings. In the affected shoots, the bark dies and exfoliates, they dry out.
Shoots with characteristic signs of damage are cut and destroyed along with pests. The soil is dug up in spring and autumn to a depth of 15 cm, and the plants should be treated with karbofos or actellik.
Raspberry, seasonal care
They choose resistant raspberry varieties for planting, carry out comprehensive measures to combat the spread of diseases on raspberry pests
- Removal and destruction of plant residues and damaged plants.
- Compliance with the necessary distances between plants.
- Timely removal of weeds.
- The use of appropriate drugs.
- In summer, the soil should be loosened.
In early spring (March-early April), raspberry pests and diseases do not damage plants. They are found in wintering places: on fallen leaves, if they were not collected in autumn, on the bark near the buds, in the upper soil layer. That is why all activities in the garden at the beginning of spring are aimed at the destruction of overwintered pests and diseases.
To eliminate the remaining fungal infection, fallen leaves are raked and destroyed. Digging the soil under the raspberry bushes destroys the wintering stages of pests (sawflies, gall flies) and fungal infections. Against diseases, treatment with copper sulfate (100 g per 10 liters of water), iron sulfate (300 g per 10 liters of water) is used.
On raspberries, pests leave their wintering places during the period of swelling and budding (end of April – May). Aphids, shoot mites, caterpillar leafworms, weevils begin to damage the emerging young leaves and buds from the eggs.
At this time, it is necessary to carefully monitor the situation in the garden, and when pests appear, take the necessary control measures in a timely manner. Raspberry beetles are shaken daily, the tips of shoots damaged by raspberry fly larvae are cut off.
Summer period (late May – September). During the flowering period of fruit and berry crops, chemical plant protection products are not used in order to preserve beneficial insects that feed on the nectar of flowers, including bees, in the garden. You can treat raspberries with insecticides only after harvesting.
After harvesting, the bushes are sprayed with a 1% Bordeaux solution (100 g of copper sulfate and 100 g of lime per 10 liters of water) against anthracnose, septoria, rust, purple and other spots on leaves and stems. Cut off and burn damaged shoots at root level to kill raspberry bud moth and stem fly.
The final pruning is done after the leaves fall in the autumn-winter period. In autumn, pests and pathogens of raspberries stop their development and prepare for wintering. Many insects hide in cracks in the bark, under fallen leaves, in the upper soil layer.
Pruning is the rehabilitation of bushes, and with the correct and timely implementation of this measure, the resistance of raspberries to diseases and pests, which often settle on a weakened plant, is strengthened. After pruning, plant residues should be burned, weeds should be removed around the bush.