Potash is a mineral compound containing potassium that farmers spread on their fields to help plants grow stronger and healthier. Just as you need certain vitamins and minerals in your diet to grow properly, plants need potassium from the soil to develop strong roots, resist disease, and produce good crops.

Today, potash comes mostly from underground deposits left behind by ancient seas. Mining companies extract it from deep mines, particularly in places like Canada and Russia, then ship it to farms around the world. Without potash fertilizer, farmers couldn't grow enough food to feed everyone, making it one of the most important minerals in modern agriculture.

The word can also refer more generally to potassium compounds used in making soap, glass, and other products. When scientists talk about potash, they're usually referring to potassium carbonate or potassium chloride, two of the most common forms.