If you’re thinking about growing cannabis plants, chances are you’ll think about pots filled with soil. However, in hydroponics, weed is grown in water instead of soil. This technique is also known as hydroculture or RDWC (Recirculating Deep Water Culture), but hydroponics is the most usual term. This method is not as complicated as many people think. Actually, growing gets easier with this technique, as plants will grow faster because they can absorb more nutrients. Hydroponics is suited for just about any plant, but it works especially well with vegetables and cannabis. This blog tells you just what hydroponics can do for you as a cannabis grower.
How Does Hydroponics Work For Cannabis Growers?
To be fair, hydroponics sounds like a pretty impressive technique. The word itself comes from the Greek concepts of ‘hydros’ and ‘ponos’ (‘water-work’; the ancient Greeks worshiped Hydros as an old god of water, and Ponos as the god of hard work). Ironically though, hydroponics done right isn’t hard work at all. Of course, it’s a matter of preference in the end, but most growers agree that hydro grows are easy once you get you get the hang of it.
Hydroponics is on the rise; mostly because it gives growers greater control over how their plants develop. Instead of growing your weed plants in soil, you grow them directly in water containing all necessary nutrients. That comes with some distinct advantages, making this technique an interesting option for advanced and amateur growers alike.
Liquid Lunch: Nutrients Straight From The Water
In hydroponics, plant roots are suspended straight in the water rather than in soil. That makes water the substrate or grow medium. Substrate is just a fancy term for ‘bottom layer’ (‘sub’ + ‘stratum’). Such layers can be anything from sand or rockwool to coco fibre, gravel, or clay pellets. In cannabis hydroponics, water is the grow medium; even if there’s a layer of clay pellets in the top section of a (floating) pot for stability. Nutrients are dissolved into the water and delivered straight to the roots. Any water that is not absorbed is recycled by the system for future use. Roots of plants grown in hydroponics tend to be longer and paler than their soil-grown counterparts, with fewer side branches. This is caused by the low oxygen content of water compared to soil.
Basically, any plant can be grown using hydroponics. Cannabis thrives on it, but these days, you’ll find entire farms growing lettuce and leeks on water alone. Fun fact: the increasing popularity of growing cannabis at home has been one of the driving forces behind the development of new hydroponics systems used in regular agriculture!
Cannabis Hydroponics Basics
The diagram below shows the basic components of a simple hydroponics setup for cannabis growers.
1: Substrate; in this case, water containing nutrients. Some systems have plants suspended directly in water, while other favour pots with a top layer of clay pellets for extra support;
2: Cover preventing evaporation and contamination of the substrate. This is usually a floating lid with holes providing a snug fit for suspended plants;
3: Aeration or oxygenation; usually in the from of an exhaust unit blowing air bubbles into the water;
4: Air pump. Many hydro setups feature a separate water pump with a filter to keep the water clean while circulating.
Different Cannabis Hydroponics Systems
The one thing all hydroponics systems have in common is the lack of soil needed to grow your cannabis plants. Hydroponics gets your cannabis plants everything they need, except light: nutrients, oxygen, and water. This can be done in several ways. Below, you’ll find a summary of the most common hydroponics systems.
(R)DWC: (Recirculating) Deep Water Culture
RDWC is the easiest system to manage, making it a great option for beginners. You put your germinated plants into individual containers, which you then place into a water container. All you add is some hydro pellets to give the roots some added grip. An air pump ensures a constant air supply into the water. Nutrients are added to the water, which the plants can then absorb through their roots. That means roots are constantly exposed to water throughout the growth cycle. The R in RDWC stands for Recirculating, because the water is constantly pumped around the system in a closed loop.
This is a slightly more complex system to use. NFT stands for Nutrient Film Technique. Here, plants grow with their roots in a wide tube, usually made of PVC. The oxygen-rich water carrying nutrients is pumped from the reservoir to the tubes and back. Tubes should be installed at an angle to ensure ample water flow back into the reservoir. The ‘Film’ in NFT represents the ideal situation in which just a thin filmy layer of water and nutrients flows over and along the roots.
This system is great at providing nutrients to your plants. If set up efficiently, it also saves water and power. One potential problem is clogged tubing due to roots blocking the flow. That gives bacteria a chance to grow, which of course will negatively impact your plants. Stay sharp while trying NFT!
Ebb And Flow System
In an ebb and flow setup, the roots are not constantly submerged. A pump regularly fills the container with oxygenated and nutrient-rich water. When the container is full, the pump stops working, allowing the water to flow back into the reservoir. It’s a bit like running your own little mangrove at home. You set the ebb and flow intervals according to what your plants need.
Drip irrigation is a popular technique among professional growers all across the agri- and horticulture sectors, but amateur homegrowers will find it very convenient, too. You feed and water your plants using a drip system. Every individual plant gets its own drip nozzle. That allows for very accurate distribution of nutrients, ensuring that every plant gets an equal share. Any liquid not absorbed by the plants flows back into the reservoir for future use.
The Benefits Of Cannabis Hydroponics
Compared to growing in soil, hydroponics can have many benefits.
- You can target your nutrition more accurately, because you don’t depend on what happens to be present in the soil. That allows you to set the perfect nutrient mix without losing valuable ingredients along the way;
- Save yourself work: no need to remove weeds, while the system makes sure your plants are fed and watered. Just keep an eye on the water level in your reservoir. Two refill a week will usually do the job. As you can see, hydroponics is perfect for lazy relaxed growers;
- Your plants will absorb the exact amounts of water and nutrients they need; no more and no less. The system simply recycles any excess water, making it a very efficient system too. Obviously, as a plant enthusiast, you care about the environment: life’s good when you can save the world by growing sustainable weed;
- Pest control: hydroponics environments are cleaner than regular soil. That limits the options for pests and bugs – one thing less to worry about;
- Better yields: plants grow better in hydroponics. For cannabis, that means better yields than for weed grown in soil, all other factors being equal;
- Rapid growth: using a hydroponics setup could reduce the growth phase of your plants by three weeks. Roughly speaking, that could mean two extra harvests every year;
- Not dependent on the weather: hot, dry summer? Freezing cold winter? It’s all the same for hydroponics, because all the plants get exactly what they need, no matter the weather. You don’t even have to keep track of the seasons – if you’re growing indoors, that is.
Drawbacks Of Hydroponics
Using hydroponics for cannabis does come with a few minor drawbacks, though. Firstly, you’ll need to spend more on equipment before you can get your system up and running. Then again, working with the right system eventually pays off in terms of saving on water and electricity.
The second and most important drawback is the tight margin for error that hydro grows offer. Soil has considerable buffer capacity: any surplus of nutrients or lack of oxygen can be compensated in part by the soil and the micro-organisms it contains. Hydroponics barely has any buffer capacity in this sense. Overdosing on nutrients or – worse – power outages will almost certainly damage your plants. That means hydroponics calls for some more vigilance from you as a grower. As long as you know what you’re getting into, though, that should not be a problem.
Outdoor Cannabis Grows Using Hydroponics
Most growers using hydroponics for their cannabis choose to do so indoors. That makes sense from the perspective of optimal control over equipment, lighting, and a bunch of other factors. Such control is slightly trickier to achieve with outdoor grows, but theoretically, hydroponics works perfectly well out in the sunshine. In fact, there are serious plans for using hydroponics as a technique for tackling global hunger issues. Of course, outdoor hydroponics calls for some extra attention to typical open-air factors like the weather, disease, and fungi, but it is certainly an option. A little greenhouse can be a big help, but you don’t strictly need one. What’s more, technology keeps improving all the time, so who knows? You could be running your own water theme park in your back garden come next grow season. At any rate, though, it’s good to know we’ll solve the world’s food problems by the efforts of weed growers such as yourself!
Getting To Grips With Hydroponics
As you’ve seen, cannabis hydroponics opens the door to carefree growing and enjoying better harvests from your weed plants. So, do you feel like starting up your own hydro grow? Give yourself the best possible start with our world-famous cannabis seeds!
Disclaimer: Local laws and legislation on cannabis cultivation and germination of seeds vary between countries and states. Amsterdam Genetics products and information are exclusively intended for use in areas where such use is fully legal. Check your local rules; do not act in conflict with the law!