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Using Potato Water on Plants: A Complete Guide

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Potato water is a nutritional kitchen byproduct that can be used to fertilize plants because the minerals it contains are necessary for growth and development in plants.

Potatoes contain minerals and nutrients that can be used to fertilize plants. Potato water can supply plants with over 350mg potassium (K) per 100g, a macronutrient used by plants to develop immunity to environmental stress along with phosphorus, magnesium, calcium, and zinc.

Potatoes are a very common vegetable in the kitchen. The peels can provide our plants with vital nutrients apart from potassium, which it is known for. 

This article explains everything the potato has to offer as well as the different methods you can use to effectively extract and add the nutrients to plants.

The Benefits of Using Potato Water on Plants

Potato Water for Plants
  • Environmentally friendly Source of fertilizer for plants
  • Easy to obtain and readily available (from Kitchen scraps)
  • Allows us to reuse waste material from the kitchen.
  • Save on the cost of purchasing Fertilizer
  • Eliminates burns associated with inorganic fertilizer application
  • Promotes healthy bacteria population within the soil
  • Can be applied through Top watering, Bottom Watering or Misting.
  • Boosts plant growth

Fun Fact:

According to the Guinness Book of World Records, the largest potato grown was 7 pounds 1 ounce by J. East (1953) and J. Busby (1982) of Great Britai

When applying water to my plants, I use a cost-effective and durable watering can that I got on Amazon, which makes watering fun and easy without any spillage. 

MyLifeUNIT Plastic Watering Can

What is Potato Water?

Potato water is nutrient-rich water obtained from boiling potatoes. 

It provides the plant with an organic source of nutrients that promotes plant growth while preventing deficiencies associated with low nutrient levels which includes brown scorching and curling of leaf tips.

It is a good source of vitamins B1, B3, and B6 and minerals such as potassium, phosphorus, and magnesium, and contains folate, pantothenic acid, and riboflavin.

These minerals form the basis of why using potato water on plants is beneficial. 

The mineral nutrients within the Potatoes are leached into the water during the boiling process. 

The high temperature of the boiling water breaks down the fibers of the potato and peel which allows the potassium, phosphorus, and magnesium to easily move into the water.

Boiling usually takes between 30 to 45 minutes to give enough time for the mineral leaching to occur. 

The water is then obtained from straining the potatoes and allowed to cool.

It is important to note that not all the minerals are removed from boiling and the peels themselves still have a good amount of minerals within them.

The peels can still be dried off and reused on plants as an additional source of slow-release minerals which we will discuss further in this article.

Fun Fact

Potatoes are grown in all 50 states of the USA and are a common vegetable in most American kitchens and are made up of about 80% water.

Parts of the Potato

Parts of the potato

How is Potato Water Beneficial for Plants: Explained

The water obtained from the Potatoes contains minerals that plants need in order to grow healthy and produce green and healthy leaves.

Carbs are the main dietary component of potatoes. Potatoes also contain small amounts of high-quality protein.

Potato water provides an economical and environmentally friendly way of supplying organically derived essential minerals to plants.

Here is a breakdown of the mineral content which can be derived from a medium-sized potato. 

Although the potato peel does not make up a significant portion of the potato, it has the same type of minerals contained in the inside portion of the potato.

The main minerals derived from the Potato are the macronutrient Potassium (K) Phosphorus (P) and the micronutrient  Magnesium(Mg).

Fun Fact

An 8 ounce baked or boiled potato has only about 100 calories.

Minerals Present in Potato

The nutrition facts for 1 medium-sized banana (100 grams):

Minerals in 100g of potato

The Benefits of Potassium in Plants

Potassium is a mineral and an electrolyte, which conducts electrical impulses in the human body. In plants, this electrolyte performs a similar task in the transportation of water and sugars.

It’s classified as a macronutrient because plants take up large quantities of potassium (K) during their life cycle. 

Other macronutrients that plants use are Nitrogen (N) and Phosphorus (P). These three are the nutrients plants need most and form the basis in the manufacture of fertilizers (NPK). 

This is why, fertilizer when bought, has a number affixed to the individual letter, which signifies the available amount of the nutrient present in the fertilizer.
X-(N), X-(P), X-(K)

Potassium Deficiency in plants

Typical symptoms of potassium deficiency in plants include brown scorching and curling of leaf tips as well as chlorosis (yellowing) between leaf veins. Purple spots may also appear on the leaf undersides. Plant growth, root development, and seed and fruit development are usually reduced in potassium-deficient plants. [Source, Wiki]

Using Potato water on plants can prevent deficiency symptoms related to low potassium levels.

Potassium helps Plants fight Pests and Diseases

Potassium helps plants develop an all-round immunity to environmental stress caused by changing weather conditions.

Plants deficient in potassium are less resistant to drought, excess water, and high and low temperatures. They are also less resistant to pests, diseases, and nematode attacks.

When used on houseplants, potassium can strengthen a plant’s resistance to fungus gnats, bacterial infections, and root rot.

Basically, it can boost a plant’s ability in dealing with over-watered conditions which can lead to the above-mentioned problems.

For the healthiest foliage, I use a cost-effective Liquid fertilizer called Purived. It helps strengthen my plant leaves, stems, and their overall health.

purvied for stronger leaves

Fun Fact:

Thomas Jefferson gets the credit for introducing “french fries†to America when he served them at a White House dinner. [Source of facts]

How to Make Potato Water?

Potato water can be made by boiling or soaking the peels in water for a period of time. Additionally, soaking the peels in water and allowing it to sit for some time can also draw the minerals out from the peels and into the water.

These are the Methods for obtaining the Potato water:

Potato water from Boiling

Use this method to obtain Potato water from boiling. The amount of peels to use depends on the amount you have available at the time.

  1. Place the peels in a cooking pot
  2. Pour water and cover 1 inch above the peels
  3. Stir properly
  4. Place on medium heat (350 oF)
  5. Allow to boil for 30 – 45 minutes
  6. Strain the peels and save the water residue

If the resulting residue is too thick you can also add water to thin it down for addition to your plants.

Potato water from Pulverizing 

Potato water obtained from pulverizing follows the same steps as from boiling (stated above).

The only difference is that the potatoes are broken up into small pieces in a blender before they are boiled.

This increases the surface area of the potato skin being exposed to boiling water. 

As a result, there is potentially a higher concentration of minerals that can be obtained from the peel using this method.

Potato Water from Soaking

Obtaining potato water from soaking requires removing the peels and leaving them in water for a period of time for the minerals from the peels to be leached into the water.


  1. Place approx 5 potatoes into a medium sized jar
  2. Fill the jar with water 
  3. Cover the lid and seal the jar
  4. Allow to sit for 10 to 15 days

The peels will turn black as time passes and the water will also change color. After the time has passed, strain the water from the peels and apply to your plants.

Tip: Breaking the peels into smaller pieces will help speed up the soaking process.

Using Pulverized Potatoes on Plants

After boiling there is still a significant amount of minerals still trapped within the peel. However, the leftover peels can still be used to maximize their benefits.

The leftover peels are dried to ensure all the moisture is removed and then pulverized into a powder or as fine as possible. This makes it easier for it to break down and release its minerals when added to the soil.

Pulverizing increases the surface area of the peels which increases the rate at which it releases nutrients into the soil. 

Adding the peels to the soil without breaking it up will allow for a much slower release of minerals into the soil as bacteria will take more time to break it down.

Method for Pulverizing Potatoes:

  1. Take the peels from 5 or more potatoes and place is in a dry area or outside in the sun
  2. Allow the peels to dry for 2 -3 days
    (the skins will become dark and hard as the water is released)
  3. Place the dried potatoes in a blender and blend for 1 minute
  4. Remove the pulverized peels and add to any plant soil around the base of the plant stem.
  5. Cover the powdered peels with soil so that the decomposition process can occur faster.

Caution must be taken when adding peels or other kitchen scraps into soil as it may cause unpleasant smells and can also attract unwanted attention from pets and lurking animals.

The peels should be buried 3-4 inches within the soil to prevent smells.

potato water for houseplants

Using Potato Water with Succulents 

Potato water can be used to water succulents while adding vital nutrients at the same time.

The mineral-rich water should be thinned so that it can be applied as a spray as succulents require more dry aerated soil. 

Succulents can be misted with a solution of potato water during their normal watering schedule. Succulents in general require a small amount of water and nutrients at any given time. 

Misting succulents with potato water is a sure method of providing them with the minerals from the potatoes without over watering and causing problems associated with overwatered soil.

How to Mist Succulents with Potato Water 

  1. Any household spray bottle can be used as long as it is cleaned properly.
  2. The water should be thin enough for the spray bottle to expel the water
  3. Add the peel water in the spray bottle
  4. Spray or mist the plant on the top as well as the underside of the leaves
  5. Also, spray the top soil with the water.

Misting should be done during the morning periods or late evenings to allow the plant to absorb moisture and nutrients. This also prevents the heat of the day from drying out the moisture too quickly.

I was surprised at how cheap I was able to buy this Plant mister spray bottle from this listing on Amazon, and it works amazingly well. You can see it by clicking here.

misting can amazon

Bottom Watering with Potato Water

Bottom watering plants with potato water is another way plants can benefit from minerals from the banana. 

Bottom watering will allow for the potato water to be absorbed thoroughly into the soil without having it in an overwatered state. 

In doing so, the total mass of the plant roots will be able to access the nutrients provided by the water.

Bottom watering is an effective method of watering plants that ensures that the entire root structure gets water without the risk of overwatering your plants. See the bottom watering plants article here.

How to Bottom Water with Potato water

  1. Use a a small, flat container two inches larger than the plant pot
  2. Place the plant into the container
  3. Add the Potato water so that the water level reaches 1 to 1 ½ inches high on the side of of the plant pot
  4. Allow the plant to sit in the water for 15 to 20 minutes
  5. After the time has passed stick your finger in and test the soil for moisture
  6. Once you feel that the soil is moist (not wet) you can remove the plant.
  7. Place the plant to drain out any excess water 

See our helpful article on how to apply fertilizer when bottom watering which will give helpful insights on how to properly add nutrients to plants when bottom watering.  

Take the guesswork out of watering plants and keeping the soil moist. It is both cost-effective and durable.
Best of all, it also measures pH and light. It’s worth a look.

Trazon Soil pH Meter 3-in-1 Soil Tester Moisture

Plants that Potato Water is Effective on

Potato water can be effective on all plants as it provides vital nutrients for plant growth. However, the method of application would differ depending on the type of plant that it is being applied to.

PlantWatering Method
Indoor PlantsMisting, Top Watering, Bottom Watering
Garden Plants Top watering, Soil application via Sprayers.

What are the Precautions When using Potato Water

When using potato water in the soil you should always ensure that the water is at ambient or room temperature so that it does not kill the bacteria in the soil and harm the plant. 

This precaution is applicable if you are using the water from boiled Potato.

Additionally, potato water is a  good additive to soil but care must be taken when watering as it can be easy to overwater the soil which can lead to root rot and yellowing of the plant leaves.

Our recommendation is to use the bottom watering method to ensure that the plant is getting the right amount of water for optimal growth.

When misting, ensure that the water is properly strained to remove banana particles that would easily clog the nozzles of the misting bottle.

Here is our article on adding fertilizer when misting which gives detailed insights on how quickly plants absorb fertilizer when applied via misting and how to correctly do it.

Using Fermented Potato Water as a Pesticide

The benefits of using fermented potato water have been proven to encourage a good bacterial population which in turn promotes healthy root growth. 

Starches found in potatoes make it easy for them to ferment and break down.

Additionally, fermented potato water produces a sour alcohol-like aroma that wards away unwanted pests like lizards, snakes, and iguanas from the garden.

Additionally, insects like fruit flies, gnats, plant lice, flea beetles, aphids, and other pests can be reduced using fermented Potato water as the alcohol from fermentation acts like an irritant to these small insects which can also kill them.

How to make Fermented Potato Water

  1. Use any available jar
  2. Fill ¾ of the contents with potato water
  3. Mix in 1 teaspoon of sugar with the water
  4. Mix in 4 tablespoons of liquid milk
  5. Cover the jar and allow it to sit for 3 – 4 days
  6. After the time has passed the solution will turn from opaque to translucent.

The resulting solution can now be used as pest control for both houseplants and in the garden.

Other Methods of Using Kitchen Scraps as Plant Fertilizers

Kitchen scraps can be used to provide plants with a cost-effective and organic means of fertilizer. 

There are many items from the kitchen that are used daily that can supply nutrients and minerals to your plants by either adding directly to the soil or by boiling or soaking in water. 

Here are a few ways and they all follow the same methodology as potato water:

Boiled Egg Water on Plants

Boiling egg shells

Eggshell water can be used to water plants because it provides the plant with calcium minerals and amino acids. Calcium is used by plants to strengthen stems and leaves while providing structural support for cell walls. Supplying a sufficient amount of calcium results in rapid and healthy plant growth.

You can find the full and detailed article here.

Watering Plants with Pasta Water

Pasta water can be used to water plants because it provides (NPK) fertilizer and minerals for plants to effectively use while promoting a healthy bacteria population. 

This results in healthy plant growth. Pasta water can also be applied using any watering method and can also ward off unwanted pests when fermented.

You can find the full and detailed article here.

Using Rice Water on Plants

Rice water can be used to water plants because it provides nutrients and minerals for plants to effectively use while promoting a healthy bacteria population. 

This results in healthy plant growth. It can also be applied using any method and can also ward off unwanted pests when fermented. 

See how this can be done from our detailed article here.

Using Banana Peel Water for plants

Banana peel water supplies plants with a substantial amount of potassium (K), a macronutrient that is used to develop immunity to environmental stress and pests.

Our detailed post on banana peel water gives an in-depth look at how it can also be beneficial for plants.

The Takeaway

Potato water can be very beneficial to plants by adding valuable minerals and nutrients to the soil. 

It helps increase bacterial growth which in turn breaks down organics compounds within the soil making nutrients easily available for plants to use.

Potato water can be obtained from either soaking the potato in water or through boiling and is a cost-effective method in providing plants with organic fertilizer.

Additionally, it can be applied through any watering method both on indoor plants and in the garden.

Potato water can also be used as a pesticide that can ward off large pests in the garden and even small flies, gnats, and flea beetles.

The overall result of using Potato water on your plants is healthy growth and increased fruit and crop production.

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