8 Super Useful Homemade Fertilizers for Indoor Plants in Water

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Growing Indoor Plants in Water is super easy, but you need to feed them often. If you’re thinking with what–these homemade fertilizers will come in handy!

Homemade Fertilizers for Indoor Plants in Water

While you can also fertilize with a pinch of water-soluble balanced feed from time to time, these Homemade Fertilizers for Indoor Plants in Water are easy, mild, and pocket-friendly.

Check out our article on 14 Powerful DIY Cucumber Fertilizers here

Why Fertilize a Water-Growing Indoor Plant?

When houseplants grow in soil, the roots can extend to larger areas and draw in all the necessary nutrients from the medium.

However, when they grow in water that you may change every 3-5 days, roots cannot find essential plant elements to grow unless you add something in water. 

Find out the Best Fruit Peels that are Brilliant Fertilizers here

When to Apply Fertilizers for Water-Grown Indoor Plants?

You can start to feed any water-grown indoor plant with a liquid fertilizer once it has formed visible roots. Fertilize once every 10 to 14 days or after every third or fourth time when you change the water. You’ll be able to discover how frequently after experimenting and growing indoor plants in water for some time.

Learn How to Make Grass Tea Fertilizer here

How to Apply Fertilizers for Water-Grown Indoor Plants?

Dilute one of these homemade fertilizers in the fresh water you’ll be filling in the vase or jar of your favorite plant at the time of changing the old water. The amount should be small; just a pinch or two of any of it would be fine.

Want to Make Organic Fertilizers from Kitchen Scraps? Click here

Homemade Fertilizers for Indoor Plants in Water

1. Eggshells 


Take 5-6 eggshells, wash them thoroughly, and air dry them for 3-5 days. Then, crush them to a fine powder. You can then add half a teaspoon of this powder into the water of the plant once a month to give an additional calcium boost. 

Find out some Excellent Eggshell Uses in the Garden here

2. Banana Peels Mix

Homemade Fertilizers for Indoor Plants in Water 2

Take 3-4 banana peels, chop them into the tiniest pieces, air dry for 5-7 days, and then grind to make a fine powder.

Keep this in a jar and add a pinch of it in the water every once in a while.

Learn more about Banana Peel Tea here

3. Used Tea


Find some used tea powder or bags and place them in a bowl. Add fresh water to fill the bowl and leave it to steep for 24 hours.

Now, dilute this with water in a 1:1 ratio and add 2 tablespoons of it to the bowl or vase in which you are growing the plant. Do this every 2-4 weeks to see the results.

Wondering if Earthworms Improve the Soil? Click here

4. Seaweed Mix

Homemade Fertilizers for Indoor Plants in Water 3

Find some seaweeds online or from the beach and wash them properly. Place them in a basket, add water till they submerge, and leave it for 30-40 days.

After this period, you can use the well-concentrated solution as an excellent homemade fertilizer. Remember to dilute it with water in a ratio of 1:4 and add 1-2 teaspoons to the vase every 6-8 weeks.  

5. Liquid Kitchen Waste Fertilizer

Using vegetable scraps, you can make this rich fertilizer loaded with minerals, calcium, and vitamins. Boil that in water and then let it cool down.

After diluting it with water in a ratio of 1:1, you can add 2-4 teaspoons of it to the vase every few weeks. It is also good for plants like lucky bamboo. 

Find out How to Use Kitchen Leftovers in the Garden here

6. Aquarium Water 


Aquarium water is the best fertilizer for your plant cuttings in water unless it is coming from a saltwater tank. It is loaded with nitrogen, phosphorous, potassium, trace nutrients, and beneficial bacteria.

Add 2-3 tablespoons of it in the vase every second time you change the water. If the water in your fish tank is very concentrated, dilute it with RO water.

Learn about Using Aquarium Water for Plants here

7. Epsom Salt

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Epsom salt helps to encourage healthier, fuller leaves and keeps the plant green even when growing in water, as it has Oxygen, Magnesium, and Sulfur. Add a pinch of Epsom salt to your water plant jar once every few weeks for the best results.

Check out some Fantastic Epsom Salt Uses in the Garden here

8. Rice Water

Homemade Fertilizers for Indoor Plants in Water 16

Rice Water is a vital source of NPK fertilizer, strengthening plant cells. Also, the fermented liquid is beneficial in warding off common houseplant pests and encouraging the growth of healthy bacteria.

Add 2-4 teaspoons of soaked rice water in the vase water every few days for best results.

Check out some Proven Rice Water Benefits for Plants here

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