The idea that salts kill plants and microbes seems very prevalent, especially among organic growers. The topic is poorly understood and leads to a number of statements that are either false or mostly false.
“Fertilizer kills plants because it is a salt”
“Farmer fields are devoid of microbes because of the salt in fertilizer”
“The NPK in manufactured fertilizer is made soluble by chemically attaching the NPK to salts”
“They [fertilizers] also make it easier for the chemicals to run off into waterways”
“Organic sources contain fewer salts”
“Organic sources are slow release”
“Fertilizers are designed to be highly soluble”
It’s time for a chemistry lesson to better understand salts, ions and the difference between synthetic and organic fertilizer.