Hydroponic gardening offers a way for growers to get creative. With so many different types of grow mediums all with their own respective advantages, there really is a grow medium for everyone. Coconut coir, perlite, and clay pebbles are all soilless substrates commonly used by hydroponic growers. Another medium that’s easily become one of the most popular is Rockwool.
Rockwool as a Grow Medium
Rockwool as a growing medium is a man-made mineral fibre. It’s created from rock that has been melted and spun until it’s become fibre much like fibreglass. These fibres are then compacted and shaped into a slab or into smaller cubes. They break apart easily and are often used right from the seedling stage. When breaking apart Rockwool slabs or cubes, be sure to wear face protection because these are tiny fibres you’re handling and you do run the risk of ingesting the dust. Rockwool is not a natural material and is therefore not biodegradable.
Benefits of Rockwool
Rockwool is a popular hydroponic substrate because it offers many important benefits required to make soilless gardening more enjoyable. Rockwool is extremely moisture retentive. It also provides great aeration allowing your plants’ root systems to obtain proper levels of oxygen.
Rockwool is also a convenient choice for growers because it breaks apart so easily you can adjust the sizes to meet your needs. Throughout the growing cycle, you can rest assured that your Rockwool substrate won’t degrade and break down over time. It will strengthen and continue to retain water properly. This is important to note because a concern is that disintegrating materials will clog up your system’s components.
Pre Treatment
Unlike most other media, Rockwool needs to be treated before it is used for hydroponics. You should soak it in pH treated water before you transfer your plants into it. For most it isn’t a major concern, it simply means that it is a bit more labour-intensive than other hydroponics media.
Health Concerns and Environment Concerns
You should be extremely cautious when handling Rockwool. It can be irritating to the skin, eyes, and lungs. Too much exposure to the skin might even cause serious long-term effects.
The skin irritation isn’t caused by any chemical danger in Rockwool, but rather its physical makeup, much like how rice leaves or grass might cause irritation if it comes in contact with the skin. To reduce your risk of any health complications, always wear a dust mask, goggles, and gloves when handling.
That same quality that makes it durable also makes it an environmental nuisance. Thrown away it does not biodegrade – It’s rock. A million years from now it will still be sitting where ever it was disposed of.
All of these Pros and Cons are important to consider when choosing your grow medium. Rockwool for its reliability and convenience makes it an excellent growing medium to use consistently from propagation to harvest.
Always stay safe and happy growing!
Related page: "Grow Your Own Food with Hydroponics
