Potassium fertilizers are compounds of potassium used as an artificial manure e.g. potassium-chloride, potassium-sulphate, potassium-magnesium-sulphate, and ashes formed after wood burns out.
Generalic, Eni. "Potassium fertilizer." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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Periodic Table