How To Grow Marijuana Hydroponically

Last updated: 7 April 2020

hydroponic weed

Although growing methods vary from grower to grower, there’s a common method that a large number of enthusiasts prefer, and that’s growing marijuana hydroponically. One of the main reasons why people prefer this method is that it offers a shorter grow time and higher yields in comparison to growing marijuana plants in soil. Although beginners may find hydroponic growing a bit tough, there’s no need to worry, as this article discusses all the ins and outs involved with hydroponic marijuana growing, allowing you to use this method without much difficulty.

Hydroponics Explained

Marijuana offers a lot of flexibility when it comes to growing. You can grow it in varying conditions and climates with the right amount of care and attention. You may find it surprising, but cannabis plants can grow without soil, too. However, they do require a sufficient quantity of nutrients and water – two things abundantly present in soil. Nonetheless, if the plants can get adequate nutrition from somewhere else, they can easily do without soil. This is essentially the main principle involved in hydroponics. The word hydroponics consists of two Greek words – hydro, meaning water, and ponics, meaning soil. Hence, hydroponic marijuana simply means growing your weed in a nutrient-dense water solution or a dormant growing medium rather than in soil.

An Efficient Alternative To Soil Growing

Growing marijuana hydroponically has tons of benefits associated with it in comparison to soil growing. It tends to deliver quicker results of higher quality buds because the process is designed specifically to provide readily-available adequate nutrients and air straight to the root of the plant. For hydroponic growing, you don’t have to be concerned about under or overwatering your plants, as a hydro reservoir proves to be more than effective during this process. Once you set up the hydroponic reservoir, you won’t need to worry about regular watering or runoff removal. 

Choosing hydroponics also gives you a lot of control over the level of pH and PPM, and open root systems allow for the efficient circulation of oxygen and nutrients. This is excellent for growers who like to tweak their plant’s nutrient intake. The timely provision of nutrients and oxygen helps the plant to grow swiftly and results in bigger yields. The reason behind the better yield is that the hydroponic process allows the grower to have more control of the quantity and quality of nutrients they provide to their plants, giving them exactly what they need to reach full yielding potential. In classic growing practices, some of the nutrients stay in the soil and cause underfeeding of the plant. Therefore, the lack of control over nutrients can often be bad for your yield. If you follow the process properly, you will attain the highest yield potential possible.

buy highest yielding cannabis strainsREAD NOW

Choose Proper Seeds For The Best Yields In Hydro

Proper strain selection is vital for effective hydroponic growing. Plants that grow in these systems absorb nutrients extremely quickly, resulting in rapid and explosive growth. Because of this, choosing a huge variety of Sativas will do you no favors, especially if your setup is inside a tent or any other indoor space. Strains that are compact and smaller are a perfect match for hydroponic systems, particularly for those indoors. It would therefore be advisable to start with smaller strains, as there are several advantages associated with it. For instance, it will allow you to cultivate multiple plants in smaller spaces, allowing for bigger yields and higher diversity. Mentioned below are a couple of strains that come highly recommended for hydroponic grows.

Royal Dwarf Auto by Royal Queen Seeds

Royal Dwarf Auto (RQS) Royal Dwarf Auto (RQS)
  • Autoflowering
  • Reaching perfect balance
  • 13 %
  • 150 - 200 g/m² indoors
    30 - 80 g/plant outdoors
Out of stock
View strain

Royal Dwarf’s yields are excellent for an autoflowering variety. This sweet strain produces yields of around 200g/m2 (0.66 oz/ft2) in under 8 weeks. The reason why this strain is perfect for hydroponic growing is because it thrives in modest indoor spaces and, due to its high sensitivity, benefits from a controlled supply of nutrients.

White Widow Auto by Kera Seeds

White Widow Auto (Kera Seeds) White Widow Auto (Kera Seeds)
  • Autoflowering
  • Forgetting all the worries
  • 16 %
  • Medium
View strain

White Widow is a proportionate mix of Sativa and Indica genetics. Its height is perfect for growing in hydro – generally, 60-100cm (1’9” to 3’2”). The strain can be grown even in Northern European climates, as the flowering period often lasts for 8 to 9 weeks.

Wedding Cake By Barney’s Farm

Wedding Cake (Barney's Farm) Wedding Cake (Barney's Farm)
  • Photoperiod
  • An energy vortex
  • 24 - 26 %
  • 650 g/m² indoors
    2000 g/plant outdoors
View strain

Since the Wedding Cake strain thrives best in indoor grow setups, where all conditions are under control of the grower, it’s also an ideal strain to grow hydroponically – in these conditions, it can yield even more than if it was grown outdoors. Even the regular version isn’t too tall for a hydroponic setup – Wedding Cake stops at 110cm (3’6”) when grown indoors.

short cannabis strainsREAD NOW

Most Efficient Hydroponic Set-Ups

Ebb And Flow

hydroponic growing

This is perhaps the most popular and simplest hydroponic system out there, the reason being that the grower doesn’t need to put in a lot of work. It’s also extremely productive and low-maintenance, making it an ideal choice for beginners. Also known as the flood and drain system, this system pumps the water/nutrient solution through a reservoir inside the system’s main part where the roots of your plant will be present. The flow will continue filling the system to the point where it gets to a dedicated overflow tube. It will bring the solution back inside the reservoir where you can pump it back into the system once again.

Drip Irrigation

hydroponic marijuana

This is an excellent way to preserve nutrients and water. The nutrients and water are provided to the plants from the top. This setup is perfect for indoor as well as outdoor growing. This irrigation system consists of small droppers that growers can be placed above their grow medium right next to the root or stem. The droppers will provide small drops of the solution to your plant consistently. This method is excellent to ensure that you don’t waste your nutrients and water by overfeeding your plant. It also helps to minimize evaporation losses. Stealth growers in particular will appreciate this setup, as it allows them to grow their plants in smaller spaces. The drip system is quite water-efficient – perfect for growers in California and other similar areas because it keeps water use to a minimum.

Deep Water Culture

 growing hydroponic weed

DWC is another simple yet effective way to grow marijuana. This method is famous for its use of air rock, which helps to provide oxygen to your plant on a consistent basis. If choosing DWC, growers need to use a large water reservoir to ensure that the plant's roots are completely and consistently submerged in water, hence the name of the method.

Must-Have List Of Tools And Supplies

A hydroponic setup requires a certain number of supplies and tools. Here are some of the tools you’ll need to ensure an effective grow.


Lights are important to ensure good results. There are various types of grow lights out there, but for hydroponic marijuana growing setups, it would be advisable to go with a 600W, 400W or 250W light. These options are ideal for first-time growers, especially if they are growing in DWC. Choose high-pressure sodium lamps (HPS) for best results from hydroponic growing. 

  • 250W lights are ideal for 1 to 4 plants. The average yield they provide is generally between 113 and 250g (4 to 9 oz).
  • 400W lights are perfect for 2 to 6 plants, and the average yield you’ll get by using these will be between 200 and 400g (7 to 14 oz).
  • 600W lights provide between 285 to 600g (10 to 21 oz) and are perfect for 2 to 8 plants.

    how to grow hydroponic weed

Provide 18 to 24 hours of light to your plant during the vegetative stage. While in the flowering stage, it would be best to keep your plants in darkness for 12 hours and under light for the remaining 12.

Grow Environment

Although a lot of growers tend to build their own growing environment from scratch, a grow tent proves to be equally handy. First-time growers particularly benefit from it, as it’s less time-consuming to start off and generally requires low maintenance.


hydroponic cannabis

You cannot neglect the importance of high-quality nutrients for hydroponic marijuana growing. Hydroguard, GH flora and Calimagic are some of the best nutritional supplements for hydroponics out there.

EC Meter And pH Meter

growing marijuana hydroponically

These meters are important to determine the correct amount of nutritional solution needed for every feeding. The EC meter tells you the correct nutrient concentration, while the pH meter helps you to determine your plant’s ability to properly transport carbohydrates and nutrients. Commercial solutions often require users to check nutrient solution concentration regularly, so don’t forget to purchase an EC and pH meter before starting your hydroponic grow.

How Good A Weed Grower Are You?TAKE QUIZ

Reservoir Tank

best plants for hydroponics

A reservoir tank is where the hydroponic system holds all of the nutrients. The tank usually also contains a water pump and an air stone. The size of the tank is determined by the type of hydroponic setup and available grow room.

Simple And Effective Setup Guide

The first thing you have to consider regarding your hydroponic grow setup is the place you want to grow your marijuana plant. Therefore, be very careful when picking a spot. Sure, a closet or an attic would be fine, but a room that’s strictly dedicated to growth would be the best option. Make sure your growing spot has good airflow, easy water access, an adequate temperature of around 20°C (60°F), and power access to run the lights. Also be sure to check that the room is properly concealed to avoid pets and pests from entering.

Every growing area needs fresh air that comes from outdoors or other rooms. If not, you’ll need to provide supplemental CO2 for replacing the CO2 consumed by plants when the lights are on. If you have a larger setup, make sure the water supply you have is close enough and provides the amount of water your plant will require. Remember to keep an exhaust fan in your growing spot. Air conditioners and air-cooled lighting are also good options.

You will also need to decide on the type of setup you wish to grow your plant in. There are various types of setups available, all with their own unique features. You need to consider the number of plants you plan to grow along with the size of the growing containers if you want to determine the right setup for your needs. Deep water culture, drip irrigation, and ebb and flow are universally-recognized hydroponic setups and some of the easiest ones to maintain.

stealth growREAD NOW

Feed Your Plant These Nutrients

how to grow hydroponic marijuana

Potassium, phosphorus and nitrogen are among the most important marijuana hydroponic nutrients. You should also be mindful about secondary nutrients, some of which are zinc, sulfur, magnesium, iron, copper, calcium and boron. You can get hydroponic nutrient supplements from various companies, whose nutrients are normally particularly designed for different growth stages. Nitrogen-based solutions are for vegetative stages; phosphorus-rich nutrients are vital for the flowering period. 

Expert growers often use the parts per million measurements to check how nutrient-dense their solution is. Remember, the lower the parts per millions, the lesser nutrients your solution contains. Mentioned below are ideal densities according to a plant’s age.

  • Early sprouts/seedlings: 100-250 parts per million
  • Early state of vegetation: 300-400 parts per million
  • Full vegetative stage: 450-700 parts per million
  • Early blooming stage: 750-450 parts per million
  • Ripening/fully mature blooming stage: 1000-1600 parts per million

Be Mindful Of This For Hydro Garden Maintenance

Checking pH and EC levels is vital to maintaining your hydro garden. Usually, if your solution's pH value is around 5.5-6.5, your plant absorbs nutrients efficiently. However, the plant could face various issues if its pH levels change too much. You can also train hydro cannabis, as training methods are not restricted only to soil growing.

Similarly, if your system’s EC levels increase significantly, it means that the plants are absorbing extra water instead of nutrients. However, if EC levels decrease, it likely means that the plants need more nutrients. You must keep a watchful eye on these measurements, as the productivity and health of your plant depend on it. Small shifts are okay, but massive fluctuations can be troublesome. Also keep a watchful eye over your system’s lights, making sure that there isn’t too much or too little of it. If your plants’ upper leaves start drying up, browning and in general appear burned, your lights are too intense for the plant and you need to move them further away.

Finally, you can harvest your marijuana plant once the process is over. If you want to experience high THC levels, harvest the plant when 60-70% of its hairs have become dark; to experience more calming effects, harvest your plant when 80-90% percent of its hairs have become dark.


Hydroponic growing can be a great experience if you take the right steps. Fortunately for you, the steps mentioned in this article will help you achieve the right yield for your marijuana plant. Be mindful of your setup, the nutrients you provide and the type of strain you choose for hydroponic marijuana growing –  these factors will all play a vital role in achieving the results you hope for.

Herbies Head Shop expressly refuses to support the use, production, or supply of illegal substances. For more details read our Legal Disclaimer.

Migue de argentina
Very good everything to follow to the letter
Hello! Thank you for the comment :)
Hello, I would like to know the diameter of the tubes for hydro culture so as not to have any problem with the roots. Thank you.
Hello Fred, You will need a medium sized plastic mesh pot if you choose the simpler method. If you want the Drip system method, standard size tubes in the ratio as shown in the picture will also work. Sincerely, Herbies
Add a comment

How to post a comment

Thank you for leaving a comment for us!

Your feedback will be posted shortly after our moderator checks it.

Please note that we don’t publish reviews that:

  • Are written in ALL CAPS
  • Use aggressive or offensive language
  • Promote other websites (include contact details or links)