You can’t grow hydroponic plants without hydroponic liquid fertilizer. Liquid fertilizer is an excellent way for your hydroponic plants to get nutrients. Unlike traditionally grown plants, there is no soil from which they can get their nutrients, and that’s the power of fertilizers, you can create the nutrients your specific crop needs “on demand”.

Read on to learn everything there is to know about hydroponic liquid fertilizers!

Can You Make Your Own Liquid Fertilizer?

Liquid fertilizer mixing in bucket for growing hydroponic vegetables

You can make your own liquid fertilizer for hydroponics. The deficiency formulas, boosters, and nutrient solutions are pretty straightforward to make. One of the perks of making your own liquid fertilizer is that you can completely tailor the fertilizer to your individual plants.

Plants don’t have a preference between man-made and organic liquid fertilizer as long as it provides the right nutrients.

When outdoor plants are growing in soil, they’re able to uptake nutrients from their surroundings. But in hydroponic systems, it’s up to you to add the right nutrients to each plant.

This includes both micronutrients and macronutrients. The proportions of each required liquid nutrient and nutrient particles can differ significantly depending on the nutrient solution suitable for the crops you’re growing.

One way to make hydroponic liquid fertilizers is to use nutrient salts. You’ll need rubber gloves, measuring spoons, and accurate scales. 

In addition, nutrients typically have pH buffers. You’ll want a pH pen along with pH Down and pH Up solutions.

You may also need an EC meter.

Having all of this dialed in will ensure happy hydroponic plants and faster growth, along with optimal vegetative growth.

How to Make Different Kinds of Liquid Fertilizer

Let’s go over a couple different ways to make liquid fertilizer for hydroponics.

Liquid Hydroponic Fertilizer

Tools needed:

  • Compost tea
  • Measuring spoons
  • Disposable filters
  • Aquarium air pump or air stone
  • 5-gallon bucket

Ingredients needed:

  • Rainwater or aquarium water
  • Compost or worm castings


  1. Put the worm casting or compost into the bucket.
  2. Fill the bucket up with water and mix until combined.
  3. Let sit for three days out of direct sunlight.
  4. Aerate the mixture with an air pump or air stone.
  5. Stir daily.
  6. Pour through disposable filters to filter out the solids.

Fertilizer-water mix

Ingredients needed:

  • 3 tablespoons of unscented Epsom salts
  • 2 teaspoons of potassium fertilizer
  • 2 teaspoons of phosphorus fertilizer
  • 2 teaspoons of nitrogen fertilizer
  • 3 gallons of water


  1. Pour all the water into a 5-gallon bucket.
  2. Add all three fertilizers, making sure there aren’t any lumps.
  3. Be sure to get fertilizers that also contain trace elements.
  4. Add the Epsom salts to provide magnesium sulfate.
  5. Mix until dissolved.
  6. Filter before use.

Deficiency Boosters

Let’s go over how to make some specific liquid plant food deficiency boosters.

Calcium Deficiency

For a calcium deficiency booster, simply crush six washed eggshells. Add one and a half liters of water along with a couple drops of hydrochloric acid.

Let it sit for a day and then filter out the shells.

Test the liquid plant fertilizer and look for a pH of about 5.

In the growth stage, this can be used along with nitrogen-rich fertilizers. In the flowering stage, this is great along with fertilizers high in phosphorus and potassium.

Potassium Boosters

To make a potassium booster, boil 3-4 banana peels in about a liter of water. Add some molasses. Sugar will work too. Let it cool and use a couple drops as needed.

When your plants are flowering, this simple potassium booster can increase growth by 20%!

Best Hydroponic Growth Enhancers

Hydroponic fertilizes AB in cup vegetable growing in agriculture hydroponic setup

Now that we’ve talked about deficiency boosters, let’s go over growth enhancers.

Coffee Ground Booster

Combine used coffee grounds with water. Let soak for a day. Filter and add the liquid to your tank during the growth stage.

This works because the bacteria that will develop on your old coffee grounds contain about 2% nitrogen and many other organic nutrients.

Root Growth with Bean Tea

Lentils and beans are chock full of compounds known as Auxins. Auxins are incredible for root growth and help leaves grow upwards.

Simply soak beans in water until they’re hydrated, then blend them until they turn into a paste.

Strain with cloth. Use bean tea for seedlings and cuttings to promote root growth.

Multipurpose Fertilizer

Take a spoonful of Brewer’s Yeast and combine it with a liter of water. Once it is dissolved, it will create phosphorus and potassium-rich solution. This will be great for any stage of growth.


Can liquid fertilizer be used for hydroponics

Liquid fertilizer can be used for hydroponics.

In hydroponics, the plants get everything they need from the direct hydroponic liquid fertilizer you give them since no soil nutrients are provided. 

This is a good thing and a bad thing. On the one hand, you can completely tailor the hydroponic liquid fertilizer to each plant you’re growing. But on the other hand, you’re responsible for making sure your plants get everything they need.

Plants need:

Macro elements.

Secondary nutrients.

Micro nutrients.

Liquid fertilizers are one way to deliver these nutrients to your plants.

Can you grow hydroponics without nutrients

You can’t grow hydroponics without hydroponics nutrients. All plants need nutrients to survive.

When you grow plants in soil, you can get away with not fertilizing because there are already nutrients in the soil. But when you grow plants hydroponically, the only way they get nutrients is through the fertilizer you provide.

What is the best fertilizer for hydroponics

The best fertilizer for hydroponics is whatever mixture matches your plant’s needs. Do some research to find out the NPK, trace minerals, and more that your plants require. 

Then you can either buy or make the fertilizer necessary for your plants to thrive!


While liquid fertilizer for hydroponics may seem daunting at first, it actually isn’t as hard as it appears. All you need to know is what nutrients your plants need and you can go from there. Now you have a solid foundation on how to provide specific nutrients to your plants if they’re in need.

Keep reading more of our blog to learn about all-things hydroponics!