Protection against spring frosts and frosts

Calendar of the nature of the middle belt for gardening

For garden crops, the damage caused by winter frosts and late spring frosts is of practical importance. The roots of garden crops are more sensitive to frost than the aboveground part, and the temperature minimum for the roots of pome and stone fruits is minus 12-14 ° C.

During winter dormancy, plant cells are much more resistant to low temperatures than during the growing season. The ability of plants to tolerate low temperatures develops in them after the completion of growth, maturation and hardening. For the hardening of perennials and the passage of the first phase it is necessary to accumulate sufficient stores of carbohydrates. Therefore, the more abundant they are supplied with nutrients, the less they are damaged by frosts. In this regard, all the effects on wood, delaying deposition of spare substances in it and ripening of wood, reduce cold resistance. These include: the late introduction of nitrogen fertilizers, causing too strong vegetative growth and preventing the timely termination of shoot growth, as well as damage to the leaf apparatus and excessive yields.

As a result of exposure to damaging winter factors in the garden, the following can be observed:

- partial or complete death of flower buds;

- freezing( to varying degrees) of annual increments, uneven-aged branches and a stem;

- damage to the bark on the stem and skeletal branches from sunburn and frostbite;

- breakage of branches due to icing and accumulation of a large mass of wet snow;

- freezing or death of roots due to deep freezing of the soil( temperature below minus 16-18 ° C) in the absence of snow cover.

- a strong disruption of plant life( with possible restoration of functions) or complete death.

Consider situations in which the gardener can take an active part in the resolution.

Take care of trees immediately after planting, especially in autumn. In the first 2 years, the near-trunk circle near the tree is better to be insulated late in the autumn( before the onset of stable severe colds) by mulching with cardboard, peat, sawdust, etc.materials.

Frosts and thick branches of trees due to the action of low temperatures can be frost-bitten, leading to the death and rupture of the cortex. Frosty breaks are observed, first of all, in cases of large variations in air temperature, when warm sunny days alternate with cold nights. Frostbroods are more susceptible to high-stamping trees, and frosty breaks are almost always found on the south and south-west sides.

Therefore, the grower must protect the tree stamps from sunlight before the start of a dangerous period of cold weather. For this purpose it is necessary: ​​to install on the stems of the net or to wrap them with nylon stockings( for young trees of pomegranates this is simultaneously protection from damage by mice), and also to whitewash with a lime solution of the following composition: for 10 liters of water, 2.5 kg of lime, 0.5kg of copper sulfate, 0.1 kg of joinery glue. You can use for this purpose a special paint grade BC-511 or "Protection".

It is advisable to renew the burrs of boles and skeletal branches early in the spring( late March - early April), when it is still possible to return cold( but not in early May, as is usually done by inexperienced gardeners).

For protection of the stem and skeletal branches from damage by strong frosts, the hilling of trees with snow will help. When hilling it should be done so that to keep under the tree crowns( to protect against frosts of the root system) a 15-20 cm layer of snow. And in the spring( in March), when thaws come, the dense snow crust of the heaps must be destroyed with the help of forks or sprinkled snow around the tree with wood ash( you can peat).

Care for the wounds of the tree bark that resulted from the frostbite should be started as soon as possible.

The wound needs to be covered with a garden or a mixture of mullein and clay, and then wrap it in a dark film( it was noticed that even the cuts in the pruning of trees quickly form a callus and cicatrize if they are wrapped in a dark film).

Regularly repeated spring frosts are a great danger to the garden, when cold returns occur after the flowering buds have opened. Apple buds die at a temperature of minus 2.8-3.9 ° C, stamens and pistils in a blossoming flower - at minus 1.5-2.5 ° C, a young ovary - at minus 1 ° C.

Flower buds usually blossom 1-5 days earlier than vegetative ones. The duration of flowering fruit trees depends on the weather conditions, but the sequence of it in the rocks is the following: cherry plum, cherry, plum, pear, apple;in berry crops - gooseberries, red currants, black currants, strawberries, raspberries. This can also determine the likelihood of damage to plants by spring frosts.

With clear sky and calm air, radiation freezes occur, characterized by strong cooling as a result of radiation. Most affected by such frost areas where cold air is accumulated - lowlands and hollows. Here the air temperature, as a rule, is 5-8 ° C lower than on an even area. If the site is located on a slope, do not make a solid fence at the bottom of it to prevent the cold air from stagnating.

The forecast of spring frosts can be made, following the change in air temperature and the state of the atmosphere.

The grid-grid for determining the probability of frosts( the numbers on the vertical axis on the right indicate the probability in%)

The most effective method by which you can raise the air temperature by 4 ° C is small-drop irrigation( continuously or with short gaps), sinceThe freezing of water liberates the heat that protects the plant from death from frost. If it is not possible to carry out the spraying, the arrangement along the perimeter of the crown of flowering trees of containers filled with water to the top will help. If the water freezes during freezing, then the ice cake should be discarded and added to the bowl of water.

In gardens with a trap, if there is a danger of frosts, it is better to cut the grass shortly, in order to reduce the thermal radiation.

Another method of combating frosts is smoke, the action of which is based on the fact that the creation of a layer of smoke prevents the dissipation of heat by radiation. The success of smoke will depend on the area protected by smoke, and on the quality of the smoke itself. The material of the smoke piles( brushwood, straw, manure, moss, etc.) should give a lot of water vapor( so humming "white smoke").To protect flowering plants from spring frosts to a 600 m2 area, approximately 8-10 smoke piles are needed for 6-7 hours of burning. Smoke begins when the air temperature drops to 1 ° C by night, and ends 1,5-2 hours after sunrise.

If the plants are slightly frozen after they are frozen, they should be sprinkled with water after sunrise - they can recover.

In the strawberry plantation from frost can save shelter plants in newspapers in 2 layers, sewn into long( up to 10 m) strip. The width of the strip is 83 cm, the strip is folded into rolls. About 40 newspapers are spent on 10 m of the ridge. You can cover strawberry ridges with stripes of old wallpaper.

Unusual advice. In order to arrest the flowering in the garden, some gardeners trample down the snow under the crown of trees and protect it from melting. This should not be done, as the above-ground part of the tree will still develop in the warm weather due to stocks in the branches, and the roots at that time will not start feeding water and nutrients. All this will lead to the exhaustion and weakening of plants. It's another matter if the horticulturist was able to cover the whole tree with snow. Then you can somewhat delay flowering and protect yourself from spring frosts.