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The Effect of Potassium Chloride on Plants

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Potassium is essential for plant growth and is one of the top three macronutrients for plants, along with nitrogen and phosphorus. Potassium chloride is a substance that has the largest quantity of potassium, according to the University of Minnesota. While potassium chloride has been shown to have some positive effects on plants, there are also some situations in which the potassium chloride can actually harm plants.


In order for a plant to have enough potassium, the potassium usually needs to be supplied in a chemical form, according to the University of Minnesota. Potassium chloride comes from underground deposits that must be mined.


Potassium is an element that is used to move carbohydrates, nutrients and water throughout the plant. The water can be used more efficiently by plants when a larger amount of potassium is present, according to the University of Minnesota. Also, when plants have more potassium, they are able to produce more protein.


Potassium is needed in order for early plants to thrive, according to the University of Minnesota. Plants that receive potassium earlier on will be more resistant to pests and diseases and will be able to survive the winter.

Expert Insight

Research has been conducted at the University of Illinois has shown that the chloride found in potassium chloride has an effect on the soybean, barley and wheat plants’ resistance to diseases. Applying potassium chloride to the soil reduced the amount of root rot that occurred with barely. However, the soils need to be able to absorb and hold the potassium chloride in order for the plants to be able to take the potassium chloride up.

Water Softner

According to the University of Wisconsin, potassium chloride might be increasingly used in water-softening systems. The current water softener, sodium chloride, puts a lot of salt into the environment. The salt from the sodium chloride leeches into the soil when the water treated with sodium chloride is inevitably released. Plants that are exposed to too much salt can become sick and even die, as seen in areas where salt treatments on snow kill plants. Potassium chloride has the same water softening effects and is actually good for plants as the largest chemical source of potassium.


According to the University of Illinois, the chloride found in potassium chloride can reduce seed germination and can also kill many young plants. After germination, the chloride in potassium chloride has had different effects on plants, with soybeans growing more rapidly after having potassium chloride applied and with wheat not being affected at all.

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