The need to understand how and with what to process grapes in the fall before winter shelter and in August after harvest often confuses beginner growers. Hydrogen peroxide and other products recommended for this can be found even in a home first aid kit, as well as purchased in specialized stores. A simple and detailed instruction will help you figure out how to properly process grapes according to the season.
Why is it necessary?
Grapes are a plant that, when cultivated, loses a significant part of its natural immunity. The vine is sensitive to climatic and temperature changes, is susceptible to fungal infections, and suffers from pest invasions. Any such influences lead to the fact that the plants stop their growth, impair the tying of bunches. The berries begin to rot, and sometimes the entire crop is destroyed.
Preventive treatments are an important component of success in viticulture. They protect plants from the development of most diseases. And also treatments can be emergency, helping to solve specific problems. The most frequently detected defeat is oidium, mildew, powdery mildew. In the absence of protection on the vine, leaves, berries, bacterial infections can develop. They are difficult to treat. Prevention is much easier. In world practice, there are many examples of the complete disappearance of certain varieties.
After phylloxera was brought to Europe from America, many vineyards were destroyed. In particular, those from which Madera was produced. They have never been able to recover. Preventive measures are the only way to protect plants. The vineyard needs to be sprayed against diseases and pests much more than other plantings on the site.
Varietal characteristics, the susceptibility of specific species to fungal infections should also be taken into account. In any case, it will not be possible to completely do without such protective measures.
Grapes are sprayed throughout its growing season. In early spring, immediately after the removal of the covering material, the first treatments are carried out. Activities are completed during the preparation of plants for wintering. But there are also certain limitations.
In autumn, grapes especially need protection after harvest and pruning. In summer, in the heat, spraying is performed only in the morning or evening hours, and in September, with the return of the rainy season, you will have to wait for dry weather to complete the treatment.
Choosing a month for the first session of protection against diseases should be based on the climate in the region. In the south, it will be the end of March or the beginning of April. In temperate regions, you will have to wait until May. It is important that the buds do not have time to bloom. Before this, dried and damaged branches are pruned, fallen leaves are removed in the root region.
The soil is sprayed along with the vine with a 1-3% solution of iron sulfate. This substance allows for effective prevention of various plant diseases, has a disinfectant effect. Spraying with iron sulphate:
- slows down the process of opening the kidneys;
- helps to avoid freezing of shoots;
- destroys mosses and lichens;
- prevents mineral deficiency.
It is traditionally believed that treatment with this substance is most useful in the fall. In the spring, it is often replaced with copper sulphate in a solution of up to 3%. Spraying is performed on a vine that suffered from diseases last season. But iron sulfate also successfully copes with its tasks, having a wider spectrum of action. The second spring treatment falls on the period when the eyes of the plant open. Fungicides are used for spraying. You can add “Karbofos” to them to destroy awakening insects. You can spray again after 10 days.
The last spring treatment should be carried out no later than 10 days before flowering, otherwise problems with pollination may occur.
The period of the most active vegetation of grapes falls on the warmest months of the year. It is important to choose the right preparations here in order to prevent the spread of the fungus, but not to lose the crop. When the atmospheric temperature rises to +18 degrees, solutions of sulfur-containing agents can be used for processing. In colder weather, they are ineffective.
After harvesting, the vine remains on the site. It is cut off, and then sprayed with solutions of iron and copper sulfate. The optimal concentration for autumn processing is 3-5%. Such a solution will prepare the grapes for wintering, provide him with high immune protection.
What to process?
Treatment of grapes for diseases can occur at different times, but it is especially important at a time when the plant is vulnerable to external influences. Some substances are used to ripen the vine, others – only after harvest, before shelter for the winter. Harvested berries are also usually processed for long-term storage.
This group of means for protecting grapes from diseases and pests includes consumables available to everyone. They help against fungus and mold, save from lichens and moss. If the vine turns black, gets sick, they may well help in the early stages.
- Boric acid. It is used during the flowering period of grapes, promotes the formation of ovaries. In the future, spraying can be carried out so that the berries are juicier. Boric acid-based fertilizing is also useful for eliminating signs of deficiency of the main active substance in the soil. The solution is prepared in hot water by immersing 2,5 g of powder in 1 liter of water.
- manganese solution. It is used to process grapes during the ripening of bunches. Every 7-14 days, foliar spraying of maturing brushes can be performed with a solution of manganese at a concentration of 5 g per 10 liters of water.
- Soda ash. A solution based on it is prepared at the rate of 50 g per 10 liters of water, adding 50 g of liquid soap and 10 drops of medical iodine. This composition can be sprayed on shoots to improve the taste of berries; when it hits the ground, it reduces the intensity of weed growth.
- Quicklime. Its solution in the proportion of 1 kg of dry matter per 10 liters of water covers the surfaces of trunks and branches. Processing is especially effective in the autumn.
- Vegetable raw materials. This includes decoctions on potato tops, onion peel, red pepper, wormwood. Raw materials are crushed, poured with water, brought to a boil. The resulting broth is filtered, stored for up to 2 months. Before use, mix with liquid solutions of soap or whey.
Separately, it is worth considering the use of hydrogen peroxide when spraying grapes. It replaces chemical fungicides during periods when clusters begin to pour on the vine. Hydrogen peroxide is safe for grapes at any stage of their development. This substance has a pronounced bactericidal and fungicidal effect, helps to compensate for the lack of oxygen in organs and tissues. The concentration of the solution varies depending on the purpose of the treatment.
- Prevention. In this case, 10 ml of 300% peroxide is added to 3 liters of water. With this composition, the vine and shoots are sprayed 3 times during the season.
- Treatment of diseases. The solution is prepared from 8 liters of water and 250 ml of hydrogen peroxide.
- Disinfection of seeds and seedlings. To soak the material in 0,5 l of water, dissolve 25 ml of the substance.
The medical solution is already sold in the required concentration of 3%. Spraying is carried out on the leaves through a garden sprayer with a fine nozzle. It is important to choose periods without bright sun or prolonged rains.
All chemicals can be used only strictly following the instructions for use. An overdose can adversely affect the condition of plants, the taste of berries. One of the safest remedies is the Bordeaux mixture, invented by the French scientist Milliardet. It is a universal fungicidal preparation that helps to destroy spores of fungal cultures. Suitable for treating diseased and healthy vines.
For spraying grapes, a number of other popular chemicals and ready-made solutions can be distinguished.
- “Fitosporin”. A drug of universal action against various infectious diseases. It is also used to increase productivity, evenly distributing treatments – up to 3 times during the season. Noteworthy is the economical “Fitosporin-M” in the form of a pasty concentrate.
- Nitrofen. A complex agent that combines the functions of a fungicide and insectoacaricidal properties. Suitable for early spring and autumn processing, used during the fruiting period. The drug inhibits the growth of weeds, but may slightly salt the soil. The composition is based on phenols obtained from coal.
- Horus. Swiss chemical preparation in the form of granules containing the substance cyprodinil. This chemical pesticide is especially active against various types of fungi – ascomycetes, deuteromycetes. The active substance has good penetration into leaves and fruits, contributes to a better preservation of the crop on the branches, and prevents rotting of the brushes. The remedy is effective against mildew, oidium, spotting and powdery mildew, fruit rot.
- Topaz. An effective preparation against white and black rot, American and rust. It is based on the substance penconazole, which does not have phytotoxicity at the correct dosage. Differs in high speed of penetration into plant tissues.
- Urea. Urea in the form of solutions saturates the soil with nitrogen. And also it is effective in processing the vineyard in early spring, destroying pathogens and insect larvae.
- “Dnok.” The preparation of complex action, suitable for the fight against insects and fungal diseases. Spraying in the spring helps prevent infection, suppress pathogenic microflora.
- Euparen. A drug of universal action. Works well with most fungal infections. Helps in the treatment of oidium, mildew, gray, white and black rot.
All fungicidal preparations for grapes are usually divided into several groups. For prevention, contact means of repeated use are well suited. But the first rain will wash away all traces of processing. Systemic drugs accumulate in plant tissues, providing long-term protection. Combined products combine the properties of the other two groups, they are best suited for the comprehensive protection of the vineyard.
The type of pathogen also matters. For example, against white and black rot, the agents “Flaton”, “Baitan”, “Tsinebom”, “Kaptan” are effective. To combat oidium and mildew, the combined preparations Vectra, Falcon, Fundazol, Ridomil Gold are more suitable. Fungicides “Sumilex” and “Topsin” are effective against gray rot.
Insecticide preparations are selected based on the type of pest attacking the vine. From a tick, aphids or phylloxera, you will need different chemicals. Each of them will take into account the peculiarities of the feeding behavior of insects. For example, in the fight against aphids, combined intestinal-contact agents work best:
- Kinmiks operating at any stage of development;
- “Aktellik” with a prolonged effect;
- “Fozalon” for long-term protection.
Spider mites can be destroyed with drugs with permethrin, benzophosphate. Concentrated colloidal sulfur (75%) will destroy any pests, including phylloxera. Against leaf rollers, “Fitoverm”, “Bitoxibacillin P” will be useful. Fufanon-Nova and other preparations based on malathion will help get rid of the worms.
The basic treatment recommendations are equally relevant for fungicides and insecticides. Spraying is best done in clear, calm weather. It is important to carefully study the instructions for the drug in order to avoid its overdose. Even the same remedy in different volumes, concentrations can become poison or medicine for grapes.
Other important recommendations.
- Maintain order in the vineyard. Before any treatment, you need to remove the fallen and yellowed foliage. The revealed signs of infection are a reason for removing damaged brushes, shoots, with their subsequent destruction.
- Compliance with the schedule. For grapes, 4 spring treatments are carried out and 1 each in summer and autumn. Unscheduled spraying will be required only if signs of infection of the vine with diseases or pests are found.
- Interchange of drugs. You can not use the same means because of the rapid addiction. It is important to regularly replace them with similar drugs, but on a different basis.
- Accounting for drug compatibility. If you need to simultaneously get rid of insects and fungus, complex preparations will come to the rescue.
- Contact protection. Some chemical pesticides can cause chemical burns if inhaled or come into contact with the skin. Wearing respirators, rubber gloves, and special suits will help prevent negative reactions.
Following these tips, you can support the immunity of grapes, take care of its safety during the fruiting period, protect valuable varieties from insect attacks, without risking your own health.