Marijuana Root Zones: Rockwool 101
Grodan rockwool is primo hydroponics root zone material! 
As a hydroponics marijuana grower, you need absolute reliability in your hydroponics root zone to get total control over how your plants absorb water, oxygen and nutrients. Fact is, what you choose as the environment for your cannabis plants’ roots is one of the main factors that determine whether you harvest lots of sticky bud, or not much.
In the old days, plants were grown in soil. Nowadays, you have hydroponics root zone options of growing in air (aeroponics), water (aquaponics) a film of water (NFT) a hybridized water system (deep water culture), soil, or inert soilless media such as rockwool or coco coir.
If you choose to have a substrate in your root zone, the top choice for professional hydroponics marijuana growers has long been rockwool. In this article and those that follow it, you’ll find out how to use rockwool to get your fastest marijuana growth and biggest yields.
Just what is rockwool? It’s like cotton candy except it’s spun from basalt rather than sugar and flavoring. The reason it’s called “rockwool” is because its texture and consistency resemble wool, and because it is made from rock.
Originally, this material was used for insulation. Researchers in Holland and other European countries where hydroponics was pioneered looked at rockwool’s consistency and realized it could be a great material for hydroponics roots.
Marijuana roots need a root zone substrate that has ample porosity so it holds air and water, as well as the right density so roots can easily grow and move throughout the material. Rockwool has those qualities.
Another rockwool benefit is that it is sterile, so there are no nutritional elements on-board. This gives you a blank slate to work with when you provide nutrition to your hydroponics plants.
It’s very important to understand how the “blank slate” effect gives you godlike control over what your plants absorb.
For example if you grow in soil, you’ve got all kinds of elements onboard in your root zone, and you really don’t know exactly what you’ve got- even if you custom-mix your soil.
These onboard elements have different ratios, forms and absorption characteristics that do not maximize what your marijuana plants can do for you when you grow in a sterile media like rockwool and use professional-grade hydroponics nutrients.
The fact is that even the most cannabis-specific customized soil mixes will give you slower growth and smaller yields when compared to a grandmaster marijuana grower growing the same marijuana plants in a properly-run rockwool system using quality hydroponics nutrients.
One thing I love about rockwool is that it is one of the few hydroponics industry products that has been scientifically tested and designed to provide you the most modernized material you can get.
The rockwool champion is the Grodan Company, based in Holland, and the fact that it’s based in Holland gives you good indication of how pro rockwool is for your marijuana.
Grodan absolutely owns the rockwool market because it has pioneered so many types of horticultural rockwool and makes the highest quality rockwool. When you watch the video embedded with this article, you'll also see that Grodan is one of few hydroponics companies that gives you helpful, free information so you get more from your hydroponics garden.
We’re talking about Grodan slabs, cubes, loose rockwool, rockwool engineered for flowering plants, rockwool engineered for wetter or drier climates…contact Grodan’s technical support people and tell them the kind of irrigation and hydroponics system you run, and they can match a variety of rockwool that’s ideal for your garden. Be sure to ask them about the need to condition rockwool before you use it so that it has the perfect pH for your marijuana crops. In most cases, you'll be using pH Down to pre-soak your rockwool so it carries a pH charge in the 5.7 to 6.3 range. Always check with your hydroponics retailer or rockwool manufacturer to find out the specifics for the rockwool you intend to buy.
If you’ve been growing in soil, supersoil, coco, or some other substrate and seeing problems with pH, ppm, nutrients absorption, watering or other factors essential to the top performance of your hydroponics marijuana plants, you owe it to yourself to consider switching to rockwool so your marijuana gardening becomes simpler, easier and more rewarding.
