Growing cannabis hydroponically simply means you grow it without using any soil. Instead, the sole source of nutrients is a water-soluble fertilizer. Although hydroponics may sound complex, it is quite easy to do once you understand a few basics. Different hydroponic weed systems are available, and you will need different items to use them, as well as nutrients and cleaning protocols.
Understanding Hydroponic Marijuana Systems
Hydroponics is the art of supplying oxygen and nutrients directly to the plant’s root system, which will allow you to grow bigger buds much faster. Although soil acts as a natural reservoir, gradually feeding nutrients while keeping the roots oxygenated, you can grow plants without it. However, soil does protect roots from various issues. When you remove it, mistakes can be very costly.
- Advantages of Hydroponics
There are major benefits to growing medical marijuana using hydroponic setups. Firstly, yields are notably bigger. Secondly, it can shorten growing time significantly, as plants grow much faster than they do in soil. Thirdly, hydroponics ensures the roots have a greater supply of oxygen. It also allows you more control over nutrients, and it is impossible to starve the plants of oxygen.
- Disadvantages of Hydroponics
The biggest disadvantage of hydroponic setups is their cost. They are much more expensive than simply buying soil. They are also more difficult to set up correctly and they require frequent maintenance. Additionally, you will need a constant electricity supply, as power shortages can stop the system from working and damage your plants, and there is almost no margin for error. Mistakes can kill your plants.
Equipment for Growing Medical Marijuana using Hydroponics
You need to consider several factors when choosing a hydroponic growing system. How much money can you afford to spend? How skilled are you? How much time do you have? Some setups require very little attention, but others require round-the-clock care. You can find two types of hydroponic systems available. We discuss them below:
- Active Hydroponic Systems
An active hydroponic setup involves using a mechanical device to move nutrient solution to the plant’s roots. Because marijuana is a fast-growing plant, it simply thrives in active setups. With just a good nutrient schedule and next to no experience, you will be able to grow huge quantities of pot. However, you will pay a lot more for an active system, and it will require a lot more of your time.
The biggest advantage of active hydroponics is the ability to grow large amounts of weed in small spaces. These clean systems do not cause nutrient buildup. However, maintaining them can be difficult and they cost a lot of money to set up. Furthermore, you have little to no buffer should you make a mistake or should an accident occur. These hydroponic systems are active:
Ebb and Flow Systems
An ebb and flow system is both simple and efficient. In fact, these systems are among the most effective for growing weed. They rely on using a nutrient reservoir to flood the roots periodically, which then, over the course of half an hour, drain out and pull in a fresh supply of oxygen in the process. The best substrate to use for this setup is either Coco Coir or Rockwool.
Deep Water Culture Systems
Deep Water Culture Systems, or Bubblers, involve suspending plants in net pots above the reservoir. To feed nutrient solution to the plant’s roots, you need an air pump to agitate it. An excess solution runs back into the reservoir, ensuring there is no wastage. Since air agitates the solution, roots have constant oxygen supply. This low-maintenance setup works best with Rockwool or clay pebble substrates.
Top Feed/Drip Feed Systems
Drip Feed, or Top Feed, hydroponic setups use various tubes, or emitters, to drip nutrient solution constantly into the medium you are using to hold the roots in place. Any excess solution simply runs through the substrate and into the reservoir, from where a pump sends it back into the system. Rockwool, Coco Coir, and Hydroton clay pebbles, are all ideal substrates for this setup.
- Passive Hydroponic Systems
A passive hydroponic setup involves suspending plants above their nutrient reservoirs and drawing solution into the medium you use to grow it. The wick or medium constantly absorbs the solution passively, which keeps it wet and continually feeding the roots. It requires the use of well-draining substrates to supply oxygen and prevent suffocating your plants.
Fortunately, passive hydroponic systems are cheap and simple to use. They are not complicated at all and, in fact, are the easiest of all hydroponic setups. However, they require the use of more nutrients than any other system does. It is paramount that you only use substrates that drain very well, such as Peat Moss, Vermiculate, Coco Coir, or a Soilless Mix.
- Aeroponic Systems
Aeroponic setups are without a doubt the most efficient way to grow pot. Bud size is frankly unrivaled. However, these systems are so big and complex that only professionals seem to use them. The setup involves suspending plants above a dark chamber, maintaining constant 100 percent humidity, and maximizing oxygen and nutrients for root absorption.
This is how complicated an aeroponic system is: To create the right humidity, you need to drop the nutrient solution onto a spinning plate, which then propels it into the air and “mists” the roots. You will need a very reliable electricity supply, and there is no buffer at all to protect the plants, which makes them vulnerable and in need of constant attention. You should only use Hydroton clay as a substrate.
Nutrients for Growing Medical Marijuana Using Hydroponics
If you are growing cannabis hydroponically, you must supply plants with all the nutrients they will require during each phase of their lifecycle. The consensus is to provide more nitrogen when plants are in their vegetative, or growing phase, and more phosphorous during their flowering stage. Watch your pH levels. Maintain them between 5.8 and 6.2 if you want your buds to grow big.
When mixing your nutrient solution, do not make it stronger than your plants can handle. Consider Electrical Conductivity, Total Dissolved Solids, or TDS, and Parts per Million, or PPM. Understanding these factors will ensure that you never starve your roots or burn them. Nutrient burn is a common problem, so always follow the manufacturer’s instructions carefully.
- Changing Nutrient Solution
It is important to change your nutrient solution occasionally. Generally, it is wise to do this at least once every two weeks, or twice a month, or when your reservoir starts drying out. Throw away the old solution, clean your pumps and reservoir with hot water, and scrub off any residue that may have built up. If you do this fortnightly, your plants should do just fine.
- Mixing Nutrients
When you mix nutrients for your hydroponic system, always make sure to add them to the water and not the water to them. If you add water to nutrients, it can cause them to “lock,” which can result in your starving your plants to death. Always check the PPM and the pH of your water to make sure it is safe to feed your marijuana plants. This guide should help you when mixing nutrients yourself:
¾ If you have any extras, add them to the reservoir. Just make sure they have finished dissolving before taking any readings. If not, it will affect the results.
¾ Using a separate bucket, mix the nutrients in a gallon of water. Never throw them directly into the reservoir, as this could “lock” them and make them unusable for your plants.
¾ When your PPMs are correct, adjust your pH levels. Always do PPMs first.
¾ Mix all nutrients extremely well, throw out the old solution quickly and replace it with the new solution.
Cleaning Hydroponic Systems Correctly
To grow strong, healthy plants and prevent pests and diseases from infesting your grow room, keep the growing environment clean. Make sure to sterilize your setup between grows, and do the same for any equipment you may be using, such as thermometers, pump filters, and air stones. Additionally, you should remove any slime and salt buildup on a weekly basis.
Too much salt and slime in the system can create a thriving environment for diseases and pests. As always, prevention is better than cure. Take the time to clean all of your tools and your reservoir tank every week, as this will help you maintain control over pest invasions and infectious diseases. These steps will help you achieve that:
- Remove all plant material from the system.
- Flush all roots and all pots or nets.
- Wash all tools vigorously. You can put them in the dishwasher. Afterward, soak them for an hour in hydrogen peroxide.
Between grows, you should also sterilize the hydroponic system itself, essentially making it new again. This will prevent any potential problems from infecting your next grow, and it will protect against the usual pests and diseases, such as aphids and mold. Follow these steps to ensure you do it properly and have a successful grow next season too:
- Wash everything with hot water.
- Spray everything with 35 percent hydrogen peroxide, not three percent, and leave it to dry.
- Flush the entire system with hot water.
- Wipe every inch of your setup with rubbing alcohol, such as 99 percent Isopropyl.
- Flush everything again with hot water to rinse.
Never use bleach to clean any part of your hydroponic setup. It leaves a dangerous residue that can contaminate your system. It is also important to wear gloves when sterilizing your equipment. Hydrogen peroxide is highly corrosive and it will burn your skin if you leave any exposed. Always remember this tip, or you will regret it when your hospital bill arrives.
In the world of cannabis cultivation, hydroponics is king. Although a lot more challenging than simply growing in soil, it is worth mastering if you want the biggest buds to grow as fast as possible. You can grow any strain hydroponically, although some do better in soil, such as tall Sativas that take an entire season to grow. If you keep these tips in mind, you should have no difficulty growing pot hydroponically.