Cheapest Hydroponic Growing Medium

Sharing is caring!

Last Updated on October 29, 2022

Just because hydroponic is a soil-free system does not mean we would not have anything to support our plants. This is why we have the hydroponic growing medium that replaces soil or dirt. So, if you’re searching for the cheapest hydroponic growing medium, then look through our guide.

We have outlined the cheapest hydroponic growing medium with the right information and some great tip to make your search easy. So, read on to know your best pick.

What Is A Hydroponic Growing Medium?

A hydroponic growing medium is a soil-free component that helps to hold sturdy or support the plant root system in the hydroponics. However, it does not provide nutrients. It is a permeable material therefore it can absorb and hold moisture, nutrients, and oxygen for the root system which is needed to grow healthily.

A hydroponic grow medium can also be a non-permeable material. You just have to increase the watering schedule so your plant root does not dry out.

Types And Characteristics Of Hydroponic Growing Medium

Before we dive into the cheapest hydroponic growing medium, let’s have an idea about the types and characteristics of some grow medium.

There are various hydroponic mediums available for your hydroponic use. Any type works great. They simply depend on the type of plant you wish to grow, the type of hydroponic system been used, and your preference.

There are so many growing mediums are accessible to suit your needs, budget, and preference. We have listed a few of the most common types of hydroponic growing medium used.

1. Rockwool

Rockwool is one soil-free hydroponic growing medium that has been in existence for a long period. It’s been longed used for plant starters and cloning. It is an inert media made from melting rock and other processes. Rockwool is meant to be pre-soaked and it has been shaped into cubes, slabs, or blocks.

Rockwool is now been used in place of starter plugs which helps in rapidly encouraging the sprouting of seeds in your farm.


2. Coco Coir

Coco coir is a famous and best-loved growing medium among hydroponic farmers. They come from the husk of coconuts and are great for hydroponic plant support and moist retention.

The soilless coco coir is loved because of its awesome characteristic protection of seed and makes them start strong. It will protect your seeds from buildup salt and too much sunlight that can harm your seeds. At the same time being a good medium free of fungi or pathogens.

3. Oasis cube

Oasis cubes is another great grow media comparable to Rockwool and they are made for both seeds and cuttings. It is an inert growing media that require no pre-soaking and has a neutral pH.

4. Expandable Clay Pebbles or Pellets

The expandable clay pebbles or pellets also called hydroton pellets is a pH neutral grow media. They are great supports for your plants which will also fit in net pots and they are reusable. Although they are not so cheap, they are cost-effective and great for your hydroponic plants.

5. Perlite

Perlite is another great media used for hydroponics. Apart from being a growing media, it is commonly used as soil additives by traditional soil growers. It is made from heating volcanic glass.

Perlite is not as good as standalone media. It is usually mixed with other grow media such as vermiculite, coco coir, as well as soil, and it’s usually mixed 50/50. Perlite is less expensive and it’s reusable.


6. Vermiculite

Vermiculite can be compared to perlites and it is made from heating mineral rocks till it expands into pebbles. It is mostly used in a mixture with other grow media.

4 Recommended Cheapest Hydroponic Growing Medium

We have listed some recommended cheapest growing medium you can go for:

1.    GROW!T JSCPB – Coco Coir Mix Brick (Pack of 3)

Grow!t coco coir mix is an awesome organic growing medium for your seeds and seedlings to germinate and start strong. It is one of the cheapest good quality coco coir and it’s easy to store and it expands very well. It is also biodegradable and renewable.

Another advantage we admire is that it offers protection against pathogens and fungi, therefore, giving your plant healthy growth. It also protects against the build-up salt.

Grow!t coco coir mix is a soil-free medium that holds water adequately and there’s no risk of plant drowning. It conveys nutrients throughout your plant root thereby improving plant development. It also has good aeration.


  • Great water retention, nutrient circulation, and aeration.
  • Offers protection for your plants.
  • Expandable and easy to store.
  • No over-saturation problems.


  • May need washing.
Cheapest Hydroponic Growing Medium - Coco Coir

2.    Grodan Mini Cubes Rockwool Hydroponic Grow Media + THCity Gloves – 2 Gallon Bag

The Grodan mini cube is a type of Rockwool and it is an inexpensive hydroponic growing medium. It comes in a cotton-like candy fiber and has been compacted into various shapes such as blocks, cubes, or slabs.

Grodan mini cube will serve as a great anchor for your hydroponic plants in their various developmental stages. This type of growing media will retain moisture and deliver nutrients to your plant root. It is great in providing good air circulation (oxygen) for the growth of your plant.

We admire the fact that it comes with a pair of lovely gloves for your comfort and protection when handling your medium.

If you wish, the cuttings or seedlings you started in Grodan mini cube can be transplanted to dirt or your soilless growing medium. Grodon will work fine if all other growing conditions are met.

The downside is that they need to be presoaked and the pH range will need to be monitored.

All in all, this is a good option you can consider when choosing the cheap hydroponic growing medium if all other conditions are met.


  • Retains moisture.
  • Delivers nutrients to plant roots.
  • Good air circulation.
  • Comes with fine pair of gloves.


  • Needs to be presoaked.

3.  1.5 inch Rockwool/Stonewool Grow Cubes

1.5 inches Rockwool is another cheap and available option for your hydroponic growing medium. It can be used for seed starters, root cuttings, and so on.

This medium provides a good anchor for your plant even for starter plants. It has great air circulation and excellent drainage properties. It also conveys nutrients to your plant root for adequate and rapid growth.

You can either use it for your garden hobby or commercial growing purpose. The size is excellent to fit into a standard flat grow tray.

Even though it requires presoaks before use, overall this is a good option you can consider when choosing the cheapest hydroponic growing medium.


  • Affordable.
  • Great for seed starters and cuttings.
  • Provides anchor for plants.
  • Great air circulations, drainage, and delivers nutrients.


  • Requires presoak.
  1. Clay Pebbles – 100g Hydroponic Clay Pebbles Growing Media Anion Clay Rocks

Clay pebble is another cheap soil-free hydroponic growing medium as well as aquaponics. It is safe and reliable and does not emit any toxic substances. They are also free from pests and diseases.

This growing medium is great support for your plant root and has excellent retention of moisture. It is as well a good transport media for nutrients. Another positive thing is that they are capable of storing nutrient and releasing it to the plant root slowly.

They might not be the best of the best, but you can work your way around it.


  • Support plants root.
  • Great water retention.
  • Great in transporting nutrients.


  • Needs washing because they are dusty.

Points To Consider When Choosing The Cheapest Growing Medium

You need to put into consideration some points when choosing the cheapest hydroponic growing medium. We have outlined these points and they will help you make the right decision.

  • Water Holding Capacity: one important point to know when choosing your growing medium is its water retention. Because nutrients are dissolved in water, the medium needs to be able to hold water and transport nutrient solution for the usefulness of your plant growth.
  • Good Anchor: because there is an absence of soil that gives support: the growing medium should be able to provide an adequate anchor to hold your plant sturdy.
  • Aeration: the growing medium must have good air circulation which is required for your plants’ growth.
  • Affordability and Availability: you should also consider if the growing medium is affordable and available in your region.

You should also note that apart from choosing the right growing medium, all other growing conditions need to be met for you to have a smooth and running hydroponic garden.

Points to Consider When Choosing the Cheapest Growing Medium


What growing medium is best for hydroponics?

One favorite growing medium is perlite. It's lightweight, easy to mix into any solution and has a great absorption rate. The only thing is that it doesn't seem to hold moisture very well. You can buy pre-mixed bags at your local gardening store. There are some good reasons to use coco coir. It's cheap, light weight, easy to mix with water and will absorb up to 5 times its weight in water. The only thing is that it is not very absorbent so you will need to add more fertilizer to it than if you were using a more absorbent medium like peat moss or vermiculite. .

Can rocks be used in hydroponics?

I would suggest using them as an addition. If you are not familiar with hydroponics, it is a method of growing plants using nutrient solutions. It works by having the roots in a solution and the plant uses the water to transport nutrients into the root system. There are two basic types of hydroponic systems: a hanging basket system and a tray system. In a tray system, the roots are grown in a tray of nutrient solution and they are submerged in the solution. The roots grow down into the solution and the solution is constantly being replaced. This is a slow growing method because the roots are growing into the nutrient solution rather than pushing through it. In a hanging basket system, the roots grow out of the nutrient solution.

Is perlite a good hydroponic medium?

Perlite is a hydrophilic, air-filled, spherical, glassy volcanic rock. It does have some beneficial qualities, but like any other growing medium it has some drawbacks too. One big drawback is that it is very light, almost weightless, so you have to hold it up for your plants or they won't grow well. Another major drawback is that it is a poor nutrient medium. It is a very poor nutrient medium. It does contain some nutrients, but the nutrients are so low in quantity that it is basically worthless as a nutrient source.
Additionally, it is a very light material and will expand when wet.

Do you need soil for hydroponics?

No, you don´t. What is the best soil for growing plants? Hydroponic systems can be a little tricky to set up, but once it’s set up and running, it’s an easy way to grow a variety of crops. If you’re planning on growing hydroponically, then you’ll need a container that will hold water and your plant roots.
These containers are called “soil-less” or “water-less.” Water-less containers are designed to be used in a hydroponic system. The main purpose of this system is to grow plants using water, rather than soil. In hydroponic gardening, you need to keep your roots constantly moist, so water-less containers are perfect for this type of gardening. It can be easy to start seeds or seedlings in a hydroponic system. This method is also great for indoor gardens.


Hydroponic growing medium supplies your plants good moisture so your plants do not dry out. They also convey nutrients and can act as a buffer in case your pump or any other essential part fails.

All in all, before you settle finally for a particular medium, try and experiment with the various medium. This way, you can pin down the appropriate growing medium for your plant’s growing needs.

Various plants have different growing needs and they will thrive with different growing mediums. Also, make sure all other growing requirements are met.

We recommend you give your system a trial and error so you can perfect all the needs of your hydroponic system.

Sharing is caring!