Types of Growing Medium

What are various types of growing medium used in hydroponics? Many gardeners would want to get an answer to this question. Unlike soil-based gardening, the growing medium in hydroponics provides physical support instead of nutrients. Most inert materials are used as growing media for hydroponics. In this case, inert materials don’t decay or breakdown quickly. Most hydroponic growing media are porous and hold oxygen and moisture vital for the roots. Here are some of the popular growing mediums for hydroponics:

#1. Rockwool

This is a favorite growing medium used in hydroponics systems. It is made of a mixture of limestone and granite melted together and spun into small cubes. However, Rockwool absorbs water and can get saturated quickly. In this case, your plants will get sufficient moisture as well as impressive amounts of oxygen. However, it is important to soak Rockwool in PH balanced water before use.

#2. Grow Rock

Also known as Hydrocom, Grow Rock is a type of clay that is subjected to high temperatures to create a porous texture. This medium is heavy enough to provide strong support for your plants. The Grow Rock holds moisture and is also non-degradable. The best thing with this growing medium is it reusability. Grow rocks can be found in most hydroponic stores.

#3. Coconut fiber

Also known as Coco Coir, this growing medium is derived from the outer husks of the coconuts. Coco coir decomposes slowly making it perfect growing medium for hydroponics. It has a neutral pH and has excellent moisture retention while allowing good aeration for the roots.

#4. Perlite

This growing medium is made of minerals that are exposed to very high heat, the expanded to form lightweight and porous material. They neutral pH and high oxygen retention, but loses moisture quickly. Perlite floats and is not suitable for some hydroponic systems such as ebb and flow system. This growing medium is known for its inexpensive price and availability at most home improvement stores.

#5. Vermiculite

Just like perlite, vermiculite is obtained from minerals that are exposed to intense heat. This growing medium can hold nutrients for later use. Moreover, Vermiculite is light and can float just like perlite. However, this medium retains too much moisture that can lead to suffocation of the plants.

#6. Pine shavings

This is an inexpensive growing medium for hydroponics that has gained popularity among growers. However, pine shavings should not be confused with sawdust. Ensure that your pine shavings are obtained from kiln dried wood and do not contain chemical fungicides. This growing medium absorbs water easily and provides better aeration to the roots. You can find good pine shavings at feed stores.

#7. River Rock

This is a cheaper growing medium found in most home improvement stores. They are non-porous and do not retain moisture. The river rock makes a perfect growing medium when used with other types of growing media. Since these rocks are uneven, they have air pockets that hold oxygen that is essential for the roots.

Growing medium provide support to the plants in hydroponics. There are many types of growing medium, and most of them are available at hydroponics stores. Each medium is unique with its advantages and disadvantages.