What temperature can grapes withstand without protection? At what temperature do you cover grapes

What temperatures can grapes without protection withstand? What temperatures do you cover grapes at?

Growing grapes is a tedious and complicated process, but the result of the efforts in the form of tasty berries is worth the time devoted to this plant. One of the most important procedures is to protect the shoots for the winter. It is necessary to find out when, at what temperature to cover, how best to carry out this event, which affects the yield of grapes in general.

Growing grapes is a tedious and complicated process.

First of all, there are varieties of grapes that need protection for the cold season and not. Frost resistance is the main property of various varieties (which can withstand d o-25-27 ° C). Nevertheless, it is necessary to cover plants, otherwise live buds will freeze. It is believed that in regions with a warm climate (at d o 16 ° C) to cover the crop is not necessary, but when the cold reaches 26 ° C, this procedure is recommended. October-November, when the first frosts arrive. Under these conditions, the vine loses its flexibility and becomes brittle. But it is better and safer to protect plants in advance if the temperature drops below 0 ° C (about t-2 – 7 C) before the first snow falls. This is the temperature of protection. Snow protects the plant from frost and is a natural “blanket” for the root system and vines. If the temperature drops to about 15°C, the ground parts of the grapes can usually live for a few days (with considerable loss of live buds), but at about 20°C winter is meaningless. Roots of grapes are covered until negative grades (d o 6 c) are applied.

At what temperature to cover grapes in the spring. Data on covering grapes by region.

Grapes are now grown in harsh Siberia, the Urals, and the Northwest. The weather in these regions determines the time to protect grapes. But from year to year winter comes everywhere at different times. How to orient yourself so as not to be too late with the construction of a shelter and at the same time not to let the bushes get steamed up? In order to have a successful winter, the mature vines should be hardened with low plus and light sub-thermal temperatures. This stimulates the immunity of the plant.

Therefore, in autumn, after the first wave of frosts, proceed to protect the grapes. At what temperature should the grapes be winterized? Experienced breeders advise to do it at outdoor temperatures from 0 to o-5 degrees. When should shelters be built in different regions?

In the North Caucasus and in the south of the Rostov region grapes are not covered at all. Winters with extreme frosts for this region occur here no more than once every 10 years. Tip! As a safety net, a partial protection can be used: insulate the root zone and put spruce branches or straw on the vines.
In the southern regions, it is not recommended to start covering earlier than the end of November – beginning of December.
In the central region and Volgara, the timing moves to early November.
In the Moscow and northwestern regions, vines should be insulated in late October.
In the Urals and Siberia and northern European regions, the weather may force a halt in early October.

But this is an average time. Every year the weather makes its adjustments, and the appropriate temperature to protect grapes for the winter is set at different times.

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There are times when you have to leave the site earlier than the optimum time for protection. In this case, you need to insulate the grapes and leave rosettes on the sides for ventilation.

What frosts the grapes’ berries can withstand. Grapes and spring frosts

Bad climatic conditions can be an obstacle to successful grape growing. Grapes and spring frosts are incompatible. Therefore, gardeners often have to look for effective ways to protect and restore plants from the harmful effects of low temperatures.

Grapes and spring frosts

Danger of frosts for grapes

Spring is not only the time of awakening of plants, but also a dangerous time of temperature changes. Thus, grapes love heat and suffer from cold, regardless of the frost resistance of the variety. Therefore, many gardeners prefer to reinsure themselves and cover their rootstock for the winter and dig them up only during a certain temperature of 8-12 ° C.

During the revival of the rootstock temperature regime can lead to frosty eyes at e-0 degrees. And this affects both the growth of the plant and the flowering period and the amount of harvest. When the vine is beaten by frost, the sap canals are frozen, and the plant is no longer getting the nutrition it needs from the ground.

Types of frosts

It is also important what type of frost came to the vineyard growing area – advection or radiation frost. Advection cooling is the most dangerous. It is very difficult to fight it, sometimes even impossible. Such frosts are characterized by several daily drops in temperature.

More common is the culture of radiative cooling, i.e. if the vines are frosted at night, they must warm up. This type of frost is more common at night and is concentrated at the surface level where the vine is growing. Such frosts can and should be dealt with.

Symptoms of Frost

Vine frost often worries gardeners in the spring, when active sap movement has already begun.

The vineyard can be seriously affected by bad weather conditions, which affects further growth and yields. The most vulnerable place is the eyeballs. It is important that replacement buds are damaged less frequently than central and fruiting buds. Annual shoots are also affected by spring frosts and hard frosts, as well as plant roots.

You can find out if a vineyard needs to be restored in early spring. You should take a knife and make incisions on the eyeballs. Those buds that are not frozen will be green in color. Those that are brown or brown in color are damaged. The enlargement of a small part of the bud suggests that the vine is shrivelled and no action needs to be taken.

The root system is more dangerous because of frost damage. To check the viability of the culture, do the following:

Dig a small hole from the bush until the roots are exposed.
Make an incision with a garden knife on the surface of one of the roots.
Check the color of the structure at the interface. It should be white. Brown or black, the plant is dead.

You should only check the roots if you see signs of frosty buds. A healthy green color indicates a healthy, unplanned root system.

Possibilities to protect plants from frost

Grapes should not be planted in a windy location

When planting the crop, measures must be taken to protect against frost. The best place for these heat-loving plants is in a wind-protected part of the garden. A house wall or an outbuilding can serve as a barrier to the wind.

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If you have an existing system to take care of, rather than a wall or other fixtures, there are some features to be aware of. To keep grapes from freezing when weather conditions worsen in the spring, you should protect them by one of the options:

Using fixtures. You can use plastic sheeting, fans, etc. You can build a small greenhouse in place of the growing shrubs and stretch the material over the bars on different sides. You can also make a removable folding greenhouse on a wooden frame or on arches. In regions where the risk of frosts is highest, such facilities are especially needed. Only when it is warm outside (at least 10 ° C), you can dig bushes out of the shelter, shake out debris, floor particles and spread them out. This should be done so that the system is ventilated. On the same day, before the cool night comes, you should build a mini-greenhouse, in which the bush will be reliably protected from frosts. It is most effective to use a mini-greenhouse on arcs. With such a shelter, you can leave a large room in the greenhouse, which will relieve the system from exchange.
Smoke. It is necessary to supply a thick smoke that heats the plants. You can use special smoke testers or build a fire.
Abundant watering and feeding. Watering should be done before the temperature drops. By evaporating, the moisture protects the plants from damage. Mineral fertilizers (except nitrogen fertilizers) have the same effect.
Spraying. Carried out with the onset of frost. There is a release of accumulators, which protect the plant from the effects of heavy frosts.
It is necessary to watch the weather conditions. Warm, quiet weather can be removed. The system should be protected overnight.

What frosts grapes can withstand. 5 simple ways to protect your vineyard from spring frosts

Late nesting and early fall frosts are not just a problem in northern regions. Albeit on a smaller scale, but it also needs to be solved in the south and in the climate of Europe

In our European North, grapes awaken in late April-May. And frosts appear at the beginning of June. Of course, the grape bushes will gradually recover, but it is additional effort, nerves and work of the grape grower. And not all varieties develop fruiting replacement eyes, so that some of the vines will not give a harvest at all this year.

Assessing “frost susceptibility” or which grapes are most susceptible to spring frosts

The susceptibility of grapes to frosts depends on the stage of shoot development.

Recently knocked out eyes and bases of flower brushes die at e-3°C.
Flower blossoms hold up to 2°C.
At the end of flowering, frost of 1.5°C is critical: berries from such frozen inflorescences will not develop.
For ovaries, frost of t-1 °С.

Losses depend on the value of negative temperature and duration of frosts. Windy weather increases the effect of cold.

Some vines cannot freeze from the outside, but under the influence of a short-term cold, they will temporarily stop growing and reduce productivity. Young grape shoots can also die on negligently covered vines because of frosts.

Pictured: grapevine shoot hit by a late spring frost

The 5 most popular ways to protect a vineyard from spring frosts

1. Smoking the vineyard

The method is relatively simple and cheap. It is effective at temperatures no lower than 4 °C.

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Fires are lit on the leeward side of the vineyard – one fire per hundred square meters. It is important that the material smolders and does not burn quickly. If you realize that a cold spell is unavoidable, the fire should be lit in the evening and made voluminous so that it does not go out in the middle of the night. At night the fire is controlled and “fed” with fuel.

But this method has one disadvantage – in a strong wind it is difficult to keep the smoke on the plot, and without wind, when the smoke rises and does not spread, its effectiveness is reduced.

2. spraying the vineyard.

In this case, water is finely sprayed over the vineyard when the temperature drops. It helps in case of frosts up to 5…-6 °С.

This method is convenient if there is a stationary irrigation system with sprayers on the plot. For shallow spraying, it is desirable to use special sprinklers, but an ordinary hose with a nozzle will do. Watering the vineyard begins 2-3 hours before the expected frost, usually late in the evening.

The essence of the effect is that when the water freezes, it releases a large amount of heat. When the temperature is low, the moisture evaporates and warms the air, which keeps the frost off the grapes.

3. Moisture replenishing irrigation of grape bushes

The essence is as follows: in the daytime, when the air temperature drops to +10 ° C, the grapes are well watered – 5 buckets per vine. In the evening, water from the heated soil begins to evaporate, warm steam rises, protecting grapes from freezing. It helps with frosts to o-5 … -6 ° C.

The effect can be intensified if you spread a transparent film under the grapes after watering, and take it off in the evening. The soil under the film heats up more, and evaporation becomes more active.

4. Pool of water between grape bushes

They are placed between the vines. The meaning is the same as in the previous option – water evaporates, the temperature near the grapes increases. It helps to o o-5°C.

5. Vineyard foliar feedings.

They can be used on young leaves in spring, but they are especially effective during early autumn frosts.The recipe is simple: dilute 3 tbsp of double superphosphate in 1 liter of hot water and leave for 3 hours.Strain. Dilute the resulting solution in 10 liters of water, add 1 tablespoon of potassium nitrate. Spray the plants 10-20 hours before the frost.

In case of unexpected frosts, add potassium and phosphorus under the root. The morning after a frost, spray subfreezing plants with zircon or epin and protect them from the sun.

The method is effective at temperatures no lower than e-4 … -5 °C.

Here’s how to find out if there will be frosts in your region.

Usually you can find out the weather forecast in the nearest town. If there is a weather station. But even on the next street in the village the temperature may differ by 2-3 ° C, for example, on the plain near the river and on a hill. However, you can predict frosts in your specific area, if not by 100%, then by 90% for sure.

In windy, overcast weather with plenty of dew or rain, frosts are unlikely.

If the sky is clear during the day and evening, and the air temperature is positive, but low around +1 … +3 °C, there is a chance it will drop below freezing at night or at dawn. Just in case, it is better to cover the grapes.

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Grapes and spring frosts

Danger of frosts for grapes

During the revival of the rootstock temperature regime can lead to frosty eyes at e-0 degrees. And this affects both the growth of the plant and the flowering period and the amount of harvest. When the vine is beaten by frost, the sap canals are frozen, and the plant is no longer getting the nutrition it needs from the ground.

Types of frosts

Symptoms of Frost

Vine frost often worries gardeners in the spring, when active sap movement has already begun.

The root system is more dangerous because of frost damage. To check the viability of the culture, do the following:

Dig a small hole from the bush until the roots are exposed.
Make an incision with a garden knife on the surface of one of the roots.
Check the color of the structure at the interface. It should be white. Brown or black, the plant is dead.

You should only check the roots if you see signs of frosty buds. A healthy green color indicates a healthy, unplanned root system.

Possibilities to protect plants from frost

Grapes should not be planted in a windy location

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Using fixtures. You can use plastic sheeting, fans, etc. You can build a small greenhouse in place of the growing shrubs and stretch the material over the bars on different sides. You can also make a removable folding greenhouse on a wooden frame or on arches. In regions where the risk of frosts is highest, such facilities are especially needed. Only when it is warm outside (at least 10 ° C), you can dig bushes out of the shelter, shake out debris, floor particles and spread them out. This should be done so that the system is ventilated. On the same day, before the cool night comes, you should build a mini-greenhouse, in which the bush will be reliably protected from frosts. It is most effective to use a mini-greenhouse on arcs. With such a shelter, you can leave a large room in the greenhouse, which will relieve the system from exchange.
Smoke. It is necessary to supply a thick smoke that heats the plants. You can use special smoke testers or build a fire.
Abundant watering and feeding. Watering should be done before the temperature drops. By evaporating, the moisture protects the plants from damage. Mineral fertilizers (except nitrogen fertilizers) have the same effect.
Spraying. Carried out with the onset of frost. There is a release of accumulators, which protect the plant from the effects of heavy frosts.
It is necessary to watch the weather conditions. Warm, quiet weather can be removed. The system should be protected overnight.

The gardener can choose an appropriate way to protect the shelters. It should be remembered that greenhouses give the longest and most reliable effect. The other methods are short-lived and can only help with frosts lasting 1-2 days.

In regions where spring frosts are not uncommon, gardeners can take appropriate measures in the fall. After the fall of leaves, bushes should be sprayed with a solution of copper sulfate. In addition to the preventive effect against pests and diseases, such an operation affects the development time of plants. A plant treated with such a solution remains for 7-10 days in the spring awakening.

Restoration of frozen bushes

The first to suffer from frost are fruit-bearing eyelets and annual shoots. Provided the root system has not been damaged by spring frosts, the bush can be restored.

In case of minor damage to the root system, gardeners recommend removing most of the vine and leaving only the root stick with the first eye from the ground. It should be buried in the ground for 1-2 weeks, so that the healthy part of the roots begins to lay down. This method will save the vineyard, but the next harvest will have to wait several years. In order for the plant to recover faster, it is recommended to water it often.

It is easier if only some parts of the bush are affected. Do not worry. As the sap starts to flow out, some of the extra buds will give young shoots. New shoots and leaves will form in a month. Unchanged shoots should be cut back.

If the grapes show no signs of life, they should be disposed of. Such a system can no longer be restored.