Does my plant have a potassium deficiency?

Potassium is the Germanic name and in many other languages ​​Kalium Potassium is mentioned. The main source of potassium is potassium carbonate, which is common in, for example, baking powder.


For humans and animals, potassium is important for transporting different things. It is also used in neurons for the electrical signal from your brain to the different parts of your body.

What is the function of potassium for the plant?

Potassium plays an important role for the plant and is indispensable for protein and carbohydrate synthesis, water management and the transport of nutrients in the plant. Especially during the flowering period the supply of potassium is extremely important and a shortage can lead to a reduced harvest. Potassium strengthens the cell tissue, increases resistance and promotes the quantity and quality of the flowering fruit. Potassium is immediately absorbable for the plant.

If the grower has to fear for one thing, it is a potassium deficiency in plants. Potassium is extremely important for the improvement of the quality characteristics, such as taste, colour, smell and shelf life of the plant's harvest.

A tomato plant with a potassium deficiency will show a bad discoloration of the tomatoes and the plant will also address a part of the water supply in the fruit, making the tomatoes softer and less flavourful.

Potassium also regulates the water absorption, this water is stored in the cell and cell tension is built up. This increases the firmness of the crop and makes the plant less sensitive to diseases, pests and more resistant to fungi.

In addition, potassium plays an important role in the functioning of the stomata of the plant, so that it is also closely involved in evaporation and absorbs CO2 that is necessary for photosynthesis.

How do you recognize the symptoms of a potassium deficiency?

A potassium deficiency in plants is sometimes called the 'edge disease'. This is because the edges of the leaves turn brown and curl up. The veins stay green for longer. Although a potassium deficiency is not common, it is important to recognize it in time.

The first symptoms of potassium deficiency in plants are expressed in a dark green plant whose leaves no longer shine optimally. They gradually become deafened and the edges of the leaves turn grey until they turn brown. The leaves then turn yellow and necrotic spots appear. Then the leaves curl and die further. When the plant is already in the flowering period, a seriously reduced flowering will be observable.

Causes of a potassium deficiency

The causes of a potassium deficiency are usually in a wrong fertilization or in the substrate. If the substrate has a too low pH value, the absorption of nutrients also decreases, so the plant also absorbs less potassium.

What can you do with a potassium deficiency?

If the substrate is too acidic, you can flush it with pH-neutral water for superfluous nutrients. In addition, an incorrect relationship between different nutrients can also be a cause of a potassium deficiency. For example, an excess of calcium and nitrogen in the substrate can lower the absorption of potassium.

By using the Atami quality plant nutrients you can be sure that your plants get the correct ratio of nitrogen, phosphorus and potassium (NPK).