How to Make Banana Peel Fertilizer

Learn how to make this simple banana peel fertilizer – it’s the perfect way to reduce waste and provides a good source of fertilizer for your garden.

Banana peels make a pretty wonderful fertilizer for potassium-loving plants in your garden.  What’s great about banana peel fertilizer is that it uses something that would normally be tossed in the trash.

Plants need a certain amount nitrogen, phosphorus and potassium in order to grow properly. Some plants need more nitrogen than others, while others need more phosphorus than others. The same goes with potassium. 

This banana peel fertilizer is such an easy way to help those potassium-loving plants and reduce waste at the same time. Especially if your kids consume a lot of bananas like mine do!

Potassium Deficiency Symptoms

A potassium deficiency in plants will lead to a few abnormalities — in most cases, they are related to growth of the plant.

Poor resistance to drought and temp changes: poor intake of potassium will affect water circulation in the plant. The plant will be less adept to temp changes and more susceptible to drought.

Chlorosis: When you notice the yellowing of the outsides of the leaves on the lower to middle plant, the plant is potassium deficient.

Defoliation: A potassium deficiency that is left untreated will lead to a loss of leaves in potassium deficient plants. This can happen quickly if there is a drought  or high temperatures. The leaves will start by turning yellow and then drop off one by one.

A potassium deficiency can also lead to poor resistance to pests, weak roots and uneven ripening of fruits.

Homemade Banana Peel Fertilizer

My kids can go through 2-3 pounds of bananas each day quite easily. I always have plenty of peels to take outside to dry in the hot sun. I leave them there in the sun for a a day or two until they are dry and brittle.

With summer temps climbing 113-114+ degrees F, there isn’t a shortage of sun.  It doesn’t take long for the peels to turn black and become crispy.

Next, bring those peels inside and use a  scissors to cut the peels into smaller pieces. The pieces need to be small enough to allow the blender or grinder to do a good job of whizzing them down into powder.

(Which reminds me: you want to be sure that the peels are not only black but also crispy. You should not be able to bend the peels – as that means there is still moisture in each one. They should snap when you try to bend them.)

Once the peels are whizzed into powder,  you’ll still have some dry bits – that’s OK. Each dried banana peel makes around 2 Tbsp of fertilizer.   Sprinkle that banana peel around the base of your plant, near the roots, taking care to water it in well. 

Since this is just a potassium fertilizer, you’ll want to do your research to find out if your plant(s) are potassium loving plants. 

Typically, plants that are grown for their flowers/fruit rather than foliage most benefit from high-potassium soils (tomatoes, squash, etc).