How Does Cannabis Hydroponics Work?

28 Nov 2022
Ecb Ec B Fed E Hydroponics

Nature, Uses and Benefits of Hydroponics In Cannabis

What Is Cannabis Hydroponics?

Cannabis Hydroponics is the art of gardening Cannabis buds without soil. Hydroponics is a Latin word meaning “working water.” In the absence of soil, water goes to work providing nutrients, hydration, and oxygen to plant life.

From watermelons to jalapeños to, of course, cannabis, plants flourish under the careful regimen of hydroponics. Using minimal space, 90% less water than traditional agriculture, and ingenious design, you can grow beautiful fruits and flowers in half the time using hydroponic gardens.

Hydroponic systems work by allowing minute control over environmental conditions like temperature and pH balance and maximized exposure to nutrients and water.

Cannabis hydroponics operates under a very simple principle: you provide plants exactly what they need when they need it. Hydroponics administer nutrient solutions tailored to the needs of the particular plant being grown. They allow you to control exactly how much light the plants receive and for how long. You can monitor and adjust pH levels. In a highly customized and controlled environment, plant growth accelerates.

First things you should probably know is that hydroponic plants grow much, much faster than those in soil. This is a prime advantage of this method of cultivation. A large reason for this is that nutrients within a hydroponic system are much more readily available to plants.

The nutrients are suspended in water and enter directly into the root system as there is no soil to navigate through. In contrast, plants growing in soil must search through the medium in order to uptake nutrients from below. Easy access to nutrients allows plants to preserve energy, which is then diverted to growth efforts instead.

Hydroponic Cannabis Nutrients

When gardening with hydroponics, you can completely control the nutrients supplied to the root system as well as the pH level. A benefit of growing hydroponically is that the roots can easily access nutrients without having to search for them. Complete control of the pH level also allows for maximum nutrient uptake by the plant. The energy saved by bringing the nutrients directly to the roots and keeping a stable pH level results in bigger and stronger plants.

The most notable difference between growing in soil and hydroponically is that soil on its own has nutrients and microorganisms that benefit the plant. When you are feeding a plant in soil, you are supplementing the nutrients while also feeding the microorganisms. If you do not feed a plant in soil, it will still grow but will not reach its full potential.

With hydroponics, you are responsible for providing all the nutrients the plant needs to survive. If you neglect nutrients the plant needs, it will die. Consequently, quality nutrients are essential when growing cannabis with hydroponics as there is no room for error.


Is Hydroponics Good for Growing Cannabis?

Have you seen cannabis plants growing with their roots just floating in a reservoir of water? This type of hydroponics is known as Deep Water Culture (DWC), and has been around for over a 100 years! As more growers gain experience with this medium, DWC has become increasingly popular for growing cannabis. Hydroponic setups are really neat and offer some big benefits over growing in soil!

Benefits of Hydro Over Soil

  • Plants grown in a hydroponic reservoir tend to grow faster in the vegetative stage, resulting in bigger yields and faster harvests
  • Hydroponic cannabis buds tend to be more potent and often cost more at dispensaries
  • Once a hydroponic reservoir is set up, it does not take a lot of work or time to maintain. Instead of regularly watering plants and removing runoff, a hydro reservoir only requires you dip a PH Pen and top off with more water or adjust as needed.
  • Less likely to get bugs
  • If growing in a reservoir, you use a very efficient amount of nutrients since you only mix up new water a few times a month. And only toss old water after the plant has already used up a lot of nutrients, which can save quite a bit if you’re using expensive nutrients and is better for the environment (compared to drain-to-waste)
  • You have more control over nutrient levels, PPM, and pH – for the mad scientists among us who want to get the most out of our plants as possible!

Cons of Hydro Over Soil

  • Takes more time and effort to set up than soil or coco. You’re providing more for the plant instead of letting the soil do some of the work for you
  • Buds grown in soil without added nutrients tend to have a stronger smell than buds grown with liquid nutrients like in a hydroponic setup (though if you’re trying to keep things low odor this might be a benefit).
  • Unless you protect your roots by using the right supplements and equipment, your plants may struggle with root rot. Consider providing your plants with a good-bacteria supplement like Hydroguard.
  • Growing in soil is more intuitive for many people, and some people already have experience with soil from other types of gardening!

Types Of Hydroponics For Cannabis

  1. Deep Water Culture (DWC)

DWC is an active recovery system, so there are moving parts. Of all active system of hydroponic growing, this is the simplest.

All you need is a net pot, a reservoir/container, a lid, and a pump.

Plants will be grown in a net pot with some growing media. They are placed and held by the lid on the top of the reservoir/container.

Roots grow out the net pot and reach the nutrient solution held in the reservoir below.

An air pump helps oxygenate the water and let roots breathe.

In order words, this system work by immersing plant’s roots directly into the nutrient solution of the reservoir that is highly oxygenated.

The cons of this system are that it does not work well with large, and long-growing plants. Very few plants other than lettuce thrive in this system.

  1. Nutrient Film Technique (NFT)

This active and recovery system is a very common hydroponic one which has been used by lots of gardeners for commercial growing.

Again, N.F.T uses the submersible pump and reusable nutrient solutions. It works by constantly flowing the solutions, so no timer is used. The nutrient is pumped into the growing tray (or a tube) and delivered to the root systems of the plants. Once the flow reaches the channel’s end, it drains back to the reservoir through the slight downward tube.

The roots suspended above the water level, are constantly moisture and get plenty of oxygen from the air surrounding them.

To provide oxygen in the water, and the grow tube, air stones or capillary matting must be placed in the reservoir. This also helps keep the system run for long without manually and frequently checking.

Since no growing medium is used, plants are usually held in a grow-basket or a supporting collar.

And because there is no growing medium to hold moisture, an extended period of interruption of the nutrient solution can make the roots dry, and plants’ death.

  1. Ebb and Flow

The active and recovery type is less commonly seen, but still quite effective.

How this system works is basically like the way it sounds. Nutrient solutions are flooded onto the plant root system and then drain periodically. And the process goes on.

Plants are grown in a tray/container with a growing medium. A timer is scheduled to turn on the pump, which pushes water with nutrient solutions in a reservoir below to rise through the tube and onto the main part of the system.

After the tray/container is filled (flooded) and soaks the plant roots at set intervals and water level, gravity automatically drains the solution back down into the reservoir.

With this system, a variety of growing medium can be used, e.g., gravel, granular Rockwool, grow rocks, perlite, etc depending on Hydroponic gardeners’ choice.

However, there is a risk of power outages, or pump and timer failure, which causes the root dryness, and water cycles are stopped.

  1. Drip System

Drip systems can be active recovery or non-recovery type system.

They are among the most common types of hydroponic systems in the world, especially for commercial growers.

The main principles behind the system are quite simple yet effective, and so their popularity.

A timer is set to schedule the submerged pump. When the timer is on, the nutrient solution is pumped and dripped onto plants’ base through a small drip line. And with this line emitter for each plant, gardeners can adjust the amount of solution per plant they want.

In a recovery drip system, the nutrient solution is sent back to the reservoir via the drip tray. Meanwhile, the non-recovery system doesn’t collect the leach-out, which is not efficient, and this is only often used in the early days of hydroponics.

However, while the recovery one can be more efficiently, and cost-effective by reusing the excess solution, non-recovery one needs less maintenance due to the same reason that solution is not recycled, and hence pH of the reservoir is not affected. By this, you can mix pH adjusted nutrient solution in the reservoir, and forget all about it, until they want to fill more. Meanwhile, with recovery, hydroponic gardeners need to check pH regularly.

Since this is a drip system, slow draining medium is often used like Rockwool, coconut coir, or peat moss

The downside of the drippers/emitters system is the clogging, which is formed by the particles from nutrients that accumulated in the emitter.

  1. Aeroponics

Aeroponic system is probably the most high-tech type of the six listed.

Just like the N.F.C system, the plant roots hang freely in the air, with no growing medium used.

But in Aeroponics, the nutrient solution is pumped and sprayed onto the root systems constantly instead of flowing through a thin film of nutrient by a channel.

A timer is used to control the nutrient pump, but the cycle is much shorter compared to other hydroponic types. Typically, it is a few minutes between each misting interval.

Again, since the roots are exposed to the air, the roots will be dried out fast in case of a misting cycle interruption. And this system is not as cheap, and easy to set up as other types.

  1. Wick System

This hydroponic technique is by far the most basic type of Hydroponic system.

Just like it sounds, the wick system operates by drawing up nutrient solutions from the reservoir to the plants through the capillary movement like a wick into the growing medium. And suitable choices of the medium include coconut fiber, perlite, or vermiculite.

The downside is that because the wick isn’t able to produce a strong stream of water, and nutrient solution, it is only ideal for smaller plants, and non-fruiting ones, like lettuce and herbs.

Also, the system tends to keep the growing medium wet. Getting too much moisture makes the oxygen absorbing activities of the plant roots become harder. The wick system is not the most effective way to hydroponic plants.


Set Up Your Hydroponic Cannabis Growing System

There are numerous setups for growing hydroponically with varying benefits that were discussed previously here. And while there are several types of hydroponic setups that don’t use any type of growing medium at all, many of them still use some sort of substrate to support root growth.

Various materials all provide slightly different benefits and drawbacks, so some thought should be put into choosing the right medium for your cannabis plants.

Before you choose your preferred system, you should start with the supplies needed. Keep in mind this depends on your space and desired results, many things can be tweaked in a hydroponic system to make it most beneficial to you. This list specifically outlines equipment needed to install your hydroponic system and does not include lights, fans, filters, and other basic needs for any grow room.

Hydroponic Cannabis Supplies:

  • 3 or 5 gallon bucket (one for each plant)
  • Grow table
  • Clay pellets (enough to fill each bucket)
  • Rockwool cubes (one 1.5-inch starter plug per plant)
  • Reservoir tank (depending on the size of garden)
  • Water pump (the bigger the better)
  • Air pump
  • Air stone
  • Plastic tubing
  • Drip line
  • Drip line emitters (one or two per plant)

Friendly Reminder; Meticulousness Is Key

Looking into the different systems, mediums, and nutrients for hydroponics can be overwhelming. However, hydroponic systems allow you to produce robust, healthy, and large plants that mature quickly by providing an ideal environment.

What cannot be stressed enough is that when growing hydroponically, you can’t cut corners with the quality of your system. Your equipment must run, your mediums must be supportive and clean, and your nutrients must be accurate. When you meet these requirements, gardening with hydroponics will yield incredible results.

Now that you have an understanding of hydroponic growing, next we’re going to explore how to best use systems and techniques for your cannabis crop. Stay tuned!

Make sure to leave your questions and share your experiences with your cannabis hydroponics in the comments! We’re excited to hear your thoughts and opinions.