Naomi Stephens | Permaculture Designer
- Dec 1, 2020
- 2 min read

What does Magnesium and Potassium deficiencies look like in plants? | Solve this with Banana Skins

Updated: Apr 5

Using the skin of a banana is cheap, easy, and convenient. I love making homemade fertiliser out of things that would otherwise be thrown in a bin. The idea of getting a second use makes it all the more rewarding.

Banana peels are rich in potassium and magnesium, using the skins are a great way of adding these nutrients to your plants.

Click on the below links to go to the sections

What does potassium do for plants?
What does potassium deficiency look like?
What does magnesium do for plants?
What does a magnesium deficiency look like?
How to use banana skins to prevent deficiencies

1.What does potassium do for plants?

Helps plants to manage periods of dryness as it regulates the uptake of water;
Necessary for activating plant enzymes;
Regulates CO2;
Needed to make Adenosine Triphosphate (ATP), which is necessary for photosynthesis and the activation of chemical processes in the plant.

Potassium is considered to be the most important nutrient for a plant second only to nitrogen.

2.What does potassium deficiency look like in plants?

It's yellowing in the leaves. Have a look at the pictures:

3. What does magnesium do for plants?

Magnesium helps plants make chlorophyll, which is responsible for the leaves being green.
Chlorophyll is needed for photosynthesis, which allows plants to get energy from the sun.

4. What does a magnesium deficiency look like in plants?

If your plants are magnesium deficient then they're going to be yellow colour on the edge of the leaves. Have a look at the examples below:

5. How to use banana skins to prevent deficiencies

Simply take a glass of bottled, distilled or rainwater and soak the banana skin overnight.
The banana skin will turn a slightly darker colour and the water will be slightly brown.
Use this water directly on your plants.