Growing cannabis is fun work. Even though growers with larger crops may groan about certain things every so often, they love what they do. This is because growing cannabis is never boring to them.
There are so many ways to grow cannabis that it’s impossible to get bored of this plant. It’s so versatile that you can even grow it in a bucket of water, literally. This is how Deep Water Culture (DWC) was created and it has become just as popular as growing in soil.
It’s a pretty easy system to set up but does have some different requirements to make it effective. With a little attention and some maintenance, even a novice grower can have beautiful autoflower plants using deep water culture.
How Does DWC Work?
DWC (deep water culture) is a branch of hydroponic growing that utilizes suspended net pots that hold your autoflower plants. The net pot is sitting over a water reservoir (usually a bucket, or tote for home growers)
As the plant grows, the roots will stretch down into the water reservoir which gives them direct access to all of the water and nutrition they need.
There are several benefits to using DWC over other growing methods, they include:
- Larger plants – With no growing medium to provide resistance, the root system of your plant can explode with growth which will ultimately give you a much larger plant. Larger plants also mean bigger yields.
- Faster Growth – The cannabis is in direct contact with the water, oxygen, and nutrients which means it can uptake anything whenever it wants. The plant will waste no time in exploding with growth without these restrictions.
- Reduced Disease And Pests – Using soil or another growing medium can harbor a lot of diseases and sometimes even house insects. Since you are using clay pellets and water, there really is no incentive for insects to live on the plant. Algae and water-borne pathogens can still exist in a DWC system.
- Minimal Maintenance – These kinds of systems pretty much take care of themselves. Since you can’t overwater your plants using this method it’s great for people who are away from their garden a lot. Autoflower cannabis doesn’t need a photoperiod adjustment which makes this a great choice to grow. Just ensure there is enough water in your reservoir and that you’re keeping an eye on nutrients.
You may be asking how the plants survive in the water when the roots require oxygen in order to avoid drowning. Oxygenating of the water is achieved through an airstone, you can even put in multiple air stones for faster growth.
While there aren’t any downsides to using DWC to grow your autoflower cannabis, there are some ways it can fail. You’ll want to keep an eye out for:
- Water Temperature – Around 19 degrees celsius is the optimal temperature for root growth. If the air pump or water pump (in a recirculating system) is generating too much heat then it could raise your water temperature too high and damage your plant’s roots. There are products on the market that chill the water in your DWC system or you could just use a couple of ice packs.
- Mechanical Failure – If any part of your air pump or water pump fizzles out then you could have a potential problem on your hand. Without oxygen, the roots will start to suffocate which can lead to stunting issues and even death.
- PH and Nutrient Imbalances – As water sits the PH will slowly rise. This is a natural process but not paying attention could cause problems like a nutrient lockout. If the water in your DWC starts to evaporate then nutrient salt concentrations could rise potentially overfeeding your gentle autoflower cannabis.
The advantages of DWC outweigh the disadvantages and even checking in on your plants a few times a week may be enough. The systems can be as simple or as complicated as you want them to be with all the risks and benefits assumed.
Deep Water Culture Vs. Recirculated Deep Water Culture Systems
DOC comes in a couple of different forms and they both serve a purpose. If you are growing a single plant or even two plants then you can stick with the regular setup. In this method, the water needs to be changed out from under the plant.
You have to drain the bucket and refill it with new nutrients and PH corrected water.
Some growers will take their plant out and put it in a separate reservoir while they change it out while others will drain it out of their system and pour new water back in. Both methods work, however moving a plant that is in late flowering can damage it.
A recirculating system is different in that the water reservoir is in a different container that has its airstone and air stone.
Gravity takes care of pushing the water into the growing container and a water pump sends it right back into the other reservoir. This effectively circulates the water through the containers.
A recirculating system is much easier to change the water out in and because of this, is effective for a large number of plants. The caveat is that more can go wrong with this system, but if you keep a tight operation running, you shouldn’t have any problems.
A word of caution though: ensure you have an extra water pump and air stone in case of mechanical failure.
They are also a little more complicated to set up so some knowledge of water pumps and different piping methods is generally an advantage in these cases.
Setting Up A DWC System
Setting up a basic DWC system for a single plant is pretty simple and can be done inexpensively. Once you have a base system implemented, you can easily expand it with minimal effort (unless you want it to be recirculating).
The items you will need to create a DWC system are:
- 5-gallon bucket (make sure it is black so that no light can get at the roots)
- An air stone
- A net pot that can fit over the bucket (hydroponic stores sell these)
- Clay pellets
- A plastic elbow for water hoses
- A small length of plastic or rubber tube
A 5-gallon bucket gives your plant a lot of room to spread its roots which will give you a large canopy and big bugs. The nice thing about autoflowers is that there is no photoperiod requirement which makes them a really good choice for autoflower.
Growing autoflowers is also a great choice for DWC because the idea is to give them optimal nutrients and airflow to let them grow, which is exactly what it does.
The clay pellets are to keep the plant straight, much like a substrate or soil medium would. Because there is so much soil for the roots to attach to, your plant can be prone to falling over if you don’t complete this step.
The plastic elbow is for the bottom of your bucket. You want to drill a hole in the side of your bucket closer to the bottom to fit this piece in. Then you attach the rubber or plastic hose to the end of the elbow.
You can then use this for draining your DWC bucket without putting your plant out. Simply rotate the tube upwards when not in use and move it down when you want to drain.
Conveniently the rubber tube (if it is translucent) will fill with water at approximately the level that it is in the bucket. This makes for a great water level indicator without you having to lift the roots out of the water and into the light.
That’s all there is to it. Autoflower cannabis grows very well in a DWC and as long as you meet these basic requirements, you can easily have a plant growing in a short time.
How often should I change the water in my DWC system?
This really depends on the amount of water that your plant is drinking. While you’re starting out a new growth you will probably be able to change your water once a week.
However, by the end of the flowering cycle, expect to add more water more than 3 times a week. This is normal and since the plant has easy access to all the water it wants, they’ll become heavy feeders.
Will my autoflower plant grow with no air stone?
This is really dependent on the plant but you should really keep an air stone in your DWC system. Your plant can become stunted and even die if there is not enough oxygen going to the roots.
If you start to notice a slow down in growing be sure to check out your airstone.
How much does it cost to start up a DWC system?
There is a range for these types of systems because it’s such a customizable way to grow autoflower cannabis. With a simple setup only needing a few basic components, you could easily get a system up and running for $50.
The more complicated the system the higher the cost with people spending thousands of dollars for sophisticated valves and timers.