a plant suffering from a potassium deficiency that is clearly visible in its leaves

Potassium deficiency

Plants suffering from a lack of potassium are smaller and have a short, limp stem. In addition, you can recognise the deficiency by smaller flower tops and pale fruits. Leaves can turn yellow or die off. This starts at the edges. There may also be brown or burned spots visible. A potassium deficiency is initially visible at the older, lower leaves. This is because potassium is mobile. This means the young leaves draw the potassium from the older leaves. Potassium deficiency results in a low yield that is also of a poor quality.

How do you recognise a potassium deficiency?

  • Plants are smaller and have a limp stem.
  • Smaller flower tops and pale fruits.
  • Leaves may have brown spots, brown veins, yellow edges or yellowing veins.
  • Plants with a potassium deficiency can absorb less water.
  • Reduced yield that is also of poor quality.

What is the (possible) cause?

  • Too little potassium in the soil or in the substrate.
  • Too much calcium or magnesium content in the soil or substrate.
  • Incorrect fertilisation.
  • Too much sodium in the root environment.

How can you prevent it?

To prevent a potassium deficiency, you can use our Bat Guano. This bat manure is very rich in potassium. Use one of our basic nutrients (like Cocos A&B) to reduce the likelihood of a deficiency. Also keep abiotic factors in mind. These include temperature, light intensity, acidity, amount of moisture and wind strength.


How can you cure it?

To stop a potassium deficiency, you can use a liquid fertiliser with a high potassium content. Examples include Green Sensation and PK 13-14.


What does potassium do for the plant?

Potassium improves the resistance of the plant and helps strengthen the cell wall. It regulates the opening and closing of stomata. These are used to regulate the absorption of carbon dioxide, water vapor and oxygen. Proper functioning of the stomata is essential to the plant. It uses them for photosynthesis, transporting nutrients and remaining cool.
an overview shot of some leaves and a stem that are suffering from a potassium deficiency
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