Here is our introductory guide to help you understand how substrates play an important role in hydro grows. Hydroponic growing is a method of cultivating cannabis in a water and nutrient solution. There are different variations on this method, with or without the help of a growing medium.
By definition, however, the plants are grown without soil. Efficiently used by the Aztecs, this method dates back to 382 B.C., where plants were fed through a nutrient solution and not a growing medium. As soil is its own ecosystem with ever-changing bacteria, nutrient quantities, and pH, it’s less reliable and stable. When dealing with just water, these variables are more easily controlled. With proper growing techniques, this process can lead to higher quality bud and better yields. Although this method involves the predominant use of water, the roots still need something to grab onto. You can’t just drop a seed into a nutrient-filled pot of water and expect it to grow. This is what we’ll be covering in this article; identifying the different growing mediums as well as their advantages and disadvantages. As you probably already know, hydro substrates do not contain nutrients.
The grower is responsible for feeding the plant through a nutrient solution in the water. The roots are in constant contact with water; the growing media is nothing but a substrate for the plant to develop a root system. This gives the plant structure and keeps the roots away from light, making them believe they’re underground. It provides great oxygenation for the root system, leading to robust health and more efficient nutrient uptake. This method has its advantages and disadvantages, obviously. With hydro plantations, growers need to be more attentive to their plants. Although plants mature quicker, nutrient deficiencies and other problems also develop faster. However, with a big enough investment, growers can set up an automated system. This will require no more than a few weekly minutes to maintain. With enough understanding, hydro plants won’t catch soil-borne diseases and are less likely to develop pest-related issues. Mediums like perlite, gravel, sand, and volcanic rock have been widely popular in hydroponic grow rooms. But with the increasing popularity of the method, new substrates have appeared on the market. Mediums like clay pebbles, rockwool, perlite, coco coir, and mapito are now being used and experimented with. Below, we’ll approach these substrates in greater detail. This is arguably the most popular growing medium in hydroponic operations nowadays. You’ve probably seen them in vases with plants and flowers of all shapes and sizes. These small, brown spheres provide excellent oxygenation for the roots. This way, they tend to grow amazingly if proper irrigation is provided. The roots aren’t placed under any stress and grow easily, making nutrient absorption extremely efficient. Make sure you find some that are already washed and have been adjusted for pH. This way, you won’t have to worry about these steps later, which is a very tedious process. An excellent insulating material and very popular in hydro plantations too, rockwool is an awesome medium for your cannabis to grow in. It has great oxygenation as well as water retention properties. Although, it takes experience and time to get everything up and running. Before placing your germinated seed, the pH of the slab must be around 5.5. To do this, immerse the rockwool in a nutrient solution with a pH of around 4.5 and an EC (Electric Conductivity)/ nutritional value of 0.5-0.6.
If the pH is not at the desired value by then, immersing the slabs again will be necessary. This should be done for a few more hours, checking regularly until the pH is stabilised.
Popular amongst Asian grow operations, coco coir results from natural waste of coconut plantations.