Apart from affecting potable water and soil fertility, sodium chloride, commonly known as salt, also influences seed germination. Usually salts present in irrigation water and soil can hinder the most significant phase of germination in plant’s life.
Seeds encapsulate all the vital elements and develop into seedlings but unless it receives proper oxygen, temperature, water, and nutrients, it may become inactive or germinate very slowly. Due to the osmotic pressure created by sodium chloride, water cannot enter the seed coat; instead, salt enters and causes toxicity to plants. This leads to underdeveloped growth and reduction in yield.
It is important for the growers to understand how salts enter their lands. Salts can enter soil through natural and human intervention, like irrigating with hard water, which contains minerals. Over time, these minerals along with those present in the soil itself increase the salinity of the soil. In areas of heavy snowfall and frost, salt is used to melt ice on various surfaces, which is then transferred to land through human feet and vehicles. Oceans contribute some of the salt content to the coastal lands. Arid lands have salt accumulation over them and due to evaporation and scanty rainfall that they receive. When it rains in such dry areas, it causes leaching of these salts deep into the soil. There are traces of sodium chloride in rainwater as well.
Don’t be disheartened if you have dry land. All you have to do is before planting seeds you can over-water it so that all the different types of mineral salts leach deep below the soil where plant roots cannot reach them. Do this a couple of times during the growing season as well. You can also put 50 pounds of gypsum for every 1,000 square feet of affected soil to aid in the leaching process. Gypsum reacts with sodium chloride to give a water-soluble and readily leachable product called sodium sulphate.
Almost all plants, whether it is vegetable, flowers and fruit trees, are stunted by sodium chloride during germination. Just that the level of resistance differs for each plant. Some are salt-resistant whereas some are very vulnerable. For example, bean growth gets affected with 960 Total Dissolved Salts (TDS) while the sugar beet is more tolerant with 5,570 TDS. However, in few plants, growth rate is not affected by salt, but still it affects its germination so it is best to germinate them indoors and then transfer them to the soil.