When the soils are eliminated, you need some materials to hold the plants as well as transmitting moisture, nutrients, and oxygen to the plants’ roots. A growing medium does that job. There are so many growing media around us. Read on to know.
What Makes a Good Growing Medium
There are limitless growing media around us. Even the air can be a great material as long as it can provide plant roots with oxygen, moisture, and nutrients.
When choosing a growing medium for your Hydroponic system, these are the great traits that you should take into account:
- Good aeration and drainage – does your medium hold the moisture and oxygen well?
- Lightweight enough to work with and carry around.
- Reusable.
- pH neutral.
- Not costly.
- Organic made and environmentally friendly.
Let’s go over some of the most popular media used in Hydroponics.
Common Types of Growing Media Used
Coconut Coir

Coconut Coir, or also called “Coco-tek”, “Cocopeat”, and “Ultrapeat” is an organic material created from the coconut shell husks.
The byproduct of the coconut industry now becomes one of the widely used media for Hydroponics.
That is because of several advantages listed below.
Pros:
- Able to hold water and the air well.
- Organic made.
- Renewable & environmentally friendly
Cons:
- Do not have good drainage. So often mix with other material.
- Uncompressed after several uses.
Perlite

Perlite has been widely used to add aeration to the soil by traditional gardeners for so long.
But this material is also one of the common medium choices in Hydroponics as well. It is created by expanding volcanic glass under extremely high temperature. Consequently, countless small white particles pop out like popcorn.
Pros:
- Lightweight
- High oxygen retention
- Reusable
Cons:
- Too lightweight for some Hydroponic systems.
- Dust from the particles.
Rockwool

Rockwool has been used popularly either by hobbyists for commercial farmers in recent years.
This material is created by melting rocks and spinning them into bundles of filament fibers.
Rockwool is a versatile inert growing medium which can be used as a standalone material and many types of Hydroponics system, especially recirculating types.
Pros:
- Hold water very well.
- Good oxygen retention.
- Has a variety of sizes and shapes
Cons:
- Not environmentally friendly – Rockwool is almost not able to dispose of.
- Dust from the particles.
- Not pH neutral.
Expanded Clay Pellets (LECA)

Expanded clay pellets are small marble shaped balls created by heating the clays until it expands into small round pellets.
Pros:
- Great oxygen retention.
- Reusable.
Cons:
- Poor water retention capacity.
- Heavy
Growstones
The porous rocks created from recycled glass is a versatile medium that can fit almost hydroponic system.
Pros:
- Great air to water ratio
- Lightweight
Cons:
- Potential damage to some plant root types because of its clinging.
- Hard to clean.
Vermiculite

Like Perlite, it’s a mined material that is made from expanded pebbles under extreme heat. It is often used in combination with perlite because of its poor drainage capacity.
Pros:
- Great moisture and nutrient retention capacity.
Cons:
- Expensive.
- Retain too much water.
Starter plugs
Starter plugs are made from organic materials like peat moss and other bioadhesive matters. This material is perfect for seed germination and plant propagation. It’s very easy to transplant to a hydroponic system.
Pros:
- Great for seedlings, and propagation phase.
- Usually organic, sustainable.
Cons:
- Quite expensive.
- Only used for seedlings or cloning.
These are not complete. But overall, start with these mediums and your hydroponic system will be fine. They have been popularly used by Hydroponic growers, but you need to take account of the pros and cons of each for your system. If you want to know more, read our post about in-depth growing media
