Two ways to desalinate and improve soil
Soil can be salty for many reasons. The main one is non-leaching soil. Solonetz soils are generally rare in the central part of Russia. This is because there is a lot of rainfall there, which leaches salts deep into the soil. However, in the south, there is less rainfall, and solonetz soils are much more common. Furthermore, heat causes water to evaporate, leaving the salts in the soil.
Soil can become salty if salt water is used for irrigation. Fertilizing also gradually adds salt to the soil, as mineral fertilizers themselves are salts.
Salinity can be combated in various ways. The simplest is by sowing green manure. Sorghum and Sudan grass are particularly effective at reducing soil salinity. Alfalfa is equally beneficial. It draws salts from the soil like a powerful pump. However, it should be planted carefully in the garden, as it competes very strongly with grapes and other trees for water and nutrients. But the fastest way to radically transform saline soil is by gypsum application. To do this, add 200-300 grams of gypsum per square meter, dig the soil thoroughly, and wait a couple of weeks for it to take effect.
Gypsum makes the salts in the soil water-soluble, which can then be washed into deeper soil layers by irrigation water. To do this, flood the garden and vineyard with water, soaking the soil to a depth of at least 70 cm. The same can be done in the vegetable garden.
Gypsum-treated soil lasts for about five years, meaning it can be washed annually, leaching the salts into the lower soil layers, where there are practically no plant roots.
The quality of gypsum application largely depends on how thoroughly the gypsum is mixed with the soil, so it's better to apply gypsum with a walk-behind tractor or cultivator instead of digging.
The best time to apply gypsum to the soil is in the fall, when the heat has subsided and moisture evaporation is minimal. It is useful to mulch the soil with straw or grass after flushing watering.