Collect the sample in a clean plastic or glass bottle. Wash or rinse the bottle at least three times with the water being sampled. For How you plan to use the water determines specific testing of samples. If you are concerned about other dissolved substances, such as nitrates, iron, and ammonia, request these tests as well. If levels of calcium, magnesium, and sodium, as well as chlorides, sulfates, and bicarbonates, as a group or alone, are too high, crop growth can be hurt.
High levels can even cause crop failure.
Often it is associated with poor soil structure. Crop growth reductions because of dissolved substances in the soil are similar to drought-stressed effects. An osmotic gradient on salty soils is formed. Water uptake by plant roots is increasingly restricted as the concentration of soil salts increases. Because of this, as soil salts build up in the soil, more frequent irrigation is necessary to help flush out salts and reduce water stress.