How to grow cannabis hydroponically?

Growers who desire to fine-tune the nutrients their plants receive opt to grow their cannabis hydroponically. By "hydroponically," we refer to the growing method wherein you grow the plants with a mixture of water and nutrients without using soil.

Arguably, hydroponics is a well-known soilless technique of tending to marijuana growth. Thanks to growers before you, this methodology has been sharpened and enhanced; there is essentially no guesswork. Due to this fact, hydroponics appeals to novice and professional cultivators alike.

How to grow cannabis hydroponically?

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What is the origin of growing cannabis hydroponically?

Cannabis was not the first plant to undergo hydroponics cultivation. The earliest record of growing soil-bound plants via soilless means is Francis Bacon’s book Sylva Sylvarum, published in 1627. Several scholars were employing "water culture" ways of growth by the early 1700s. Hydroponics is primarily used for research during its early years because we didn’t know which fertilizers and minerals plants require.

By the name of Julius von Sachs and Wilhelm Knop, two German botanists developed a particular water culture methodology wherein you bubble air using a nutrient-rich solution of water. Today, this technique is known as deep water culture (DWC), although people called it solution culture before.

The appreciation of hydroponics’ power in growing plants did not come until the 1900s. Then, growers began to realize that hydroponics is the secret to achieving faster and healthier growth. Compared with plants grown on Earth, in hydroponics, the grower can supply essential nutrients directly to the plant at the proper time.

Why should I grow cannabis hydroponically?

Hydroponics promise growers numerous benefits that soil-oriented techniques cannot provide. The advantages soilless cultivation brings attracted the attention of many marijuana cultivators. Below are some of them:

1) Faster growth – When you grow your plants using hydroponics, there is a possibility of experiencing a 30 – 50% increase in their growth rate. The most common reason for such expedited development is that your plants receive everything they need in a very suitable condition. There are no days with clouds. There are no droughts. There are no nutritional deficits. Instead, thanks to a regular supply of high-nutrient liquid fertilizer, your vegetables have a nutritional smorgasbord!

2) Easy to manage – Growers utilizing a soilless technique have fewer areas of concern compared with their counterparts. In hydroponics, you can alter the factors that affect a suitable environment for marijuana conveniently. These factors are light, temperature, humidity, pH levels, nutrients, and water. Hydroponic gardening is more accessible and less time-consuming than earth gardening because of managing these elements.

3) Less pest control – Another benefit of hydroponics that is noteworthy to expert growers is the lesser pest management involved. If you think of it, pests have fewer entry points in a hydroponic setup because of the closed environment. As a result, insects have more difficulty infiltrating your strains, destroying them eventually. Moreover, lesser pests mean lesser pesticides on your plants.

4) Direct feeding of nutrients – Plants receive their essential nutrients directly in a hydroponic setup. The fertilizer is in a liquid solution form, and once you introduce it into the aqueous system, the roots have direct contact with the nutrients.

5) Larger harvest yield – The best thing about hydroponics planting is it provides you with larger produce. Experienced growers attest to this fact because of the fast growth rate you can get from soilless cultivation. One of the main reasons for this is that plants in a hydroponic system have significantly more accessible nutrients. Because there is no dirt to traverse through, the nutrients are suspended in water and delivered directly to the root system. Therefore, plants can conserve energy by having easy access to nutrients. On the other hand, plants growing on soil must hunt through the substrate for nutrients from below.

Hydroponics offers marijuana growers many benefits, just like its organic counterpart. These gains are why modern-day producers choose the hydroponic way of tending to their cannabis growth instead of doing it organically speaking. If you are interested in growing cannabis the organic way, you should check out this blog post.

What are the ways of growing cannabis hydroponically?

There is more than one way to cultivate cannabis, hydroponically speaking. Thanks to today’s technology, one can choose from four types of soilless systems available now for every grower. Let us discuss each of them:

1) Wick system

Wick hydroponic systems are the simplest to put up and operate among all the systems listed here, and they are usually the cheapest. A functioning wick system is achievable as long as capillary action is active. Like any good game, a decent system takes a few minutes to understand but a lifetime to master.

How does the wick system work?

The principle of capillary action governs the operation of a wick system. Capillary action refers to the mechanism through which liquids ascend through another material against gravity. For example, it’s how an oil lamp works, drawing the oil up the wick as the flame burns it off.

The wicks in a hydroponic wick system transmit the nutrient solution to the plant roots, in the same way, ensuring that the plant has access to water and food at all times. The nutrients are drawn up the wick from the reservoir as the plant draws them in with its roots. It is not possible to overwater a wick system plant since it supplies the power to lift the solution.

What are the advantages of the wick system?

Generally speaking, the wick system is novice-friendly. While you’ll still need a basic understanding of producing cannabis, wick systems eliminate some issues that can be difficult for inexperienced growers.

As a passive system, the wick setup avoids overwatering, which is a common concern for beginners in cannabis cultivation. 

Finally, while complete kits are available, one can prepare a wick system from everyday home items. The risk of things falling or breaking is extremely low due to the lack of moving parts.

What are the disadvantages of the wick system?

The wick system has its share of drawbacks that growers should understand. Here are some of them:

The wick system is ineffective for bigger plants. Every experienced grower agrees with this.

The growing medium does retain nutrients that would eventually lead to mineral salt buildup. If not addressed immediately, this situation is toxic for your plants.

Constant inspection is needed because of mold growth which directly affects the health of your cannabis growth.

2) Ebb and flow

Due to its ease of use, cheap maintenance, and high yield, the ebb and flow technique, also known as flow and drain, is one of the most popular hydroponic systems for growing marijuana. The method entails growing a plant in a medium that allows it to create its stem and roots. The roots will then develop as they move through the growing media and down to the nutrition water source.

Both newbie and expert growers use the ebb and flow for growing their marijuana because a rudimentary level of technical knowledge would be enough for this hydroponics system.

How does ebb and flow hydroponics work?

Ebb and flow systems often include a plant tray where the grower places the plants. Marijuana can be grown in pots with a proper growth material or by filling the tray with growing mix and planting the plants directly in it. You periodically supply into the tray. A water pump with a timer achieves such a setup. After the set time, the solution drains into the reservoir. A simple overflow outlet keeps the tray from overfilling, preventing overflow and floods in your grow room.

What are the advantages of ebb and flow?

The automation of ebb and flow is one of its notable features. The setup takes care of itself, and you have fewer maintenance efforts to put into it. The affordability to construct this technique is also worthy of mentioning. Lastly, cultivators love the ebb and flow methodology for its simplicity: it is quiet, takes up little space, and uses minimal energy. Ebb and flow is a fantastic option if you want your hydroponics system to remain unobtrusive.

What are the disadvantages of ebb and flow?

The known disadvantage of ebb and flow is that your entire crop becomes affected if something goes awry. There is also a risk of root diseases and nutrient deficiency. A situation like this could be the result of sanitation and maintenance negligence.

If you are considering the ebb and flow system, visit this store. They offer pre-made ebb and flow setups that you can use with ease and comfort.

3) Deepwater culture 

Deep Water Culture (DWC) is a hydroponic growth method that does not require a medium. Growers suspend their plants in specialized pots or nets with their roots extending down into a pool of aerated, nutrient-rich water in a DWC system. When compared to other growing methods, producing cannabis in a DWC system has a lot of advantages.

How does DWC work?

Deep Water Culture is the name given to this approach for two reasons. To begin with, you’ll need a reservoir that can contain a reasonable amount of water. More water in your fertilizer solution equals more stability, which means less monitoring and maintenance for you.

The second explanation is the amount of root mass that you submerge in the water. The majority of your plant’s root system remains immersed 24 hours a day, seven days a week in deep water culture – hence the name! Other options involve exposing your plant’s root zone to air and soaking it in the water a few times per day (ebb and flow systems are an excellent example of this).

What are the advantages of DWC?

Growers using DWC experience faster vegetative growth as well as bigger yields. A good explanation for this is because the plants have easier access to oxygen and vital nutrients. As a result, there is lesser time spent searching for nutrients and root development. Thus, the best incentives are an expedited vegetative process and sizable yields.

Pests become less of your problems in DWC setups. The absence of any growing medium explains this agreeable circumstance. Another upside of a medium-less system is that it is not high maintenance. If your DWC is up and running, you can leave it for over 24 hours on its own.

What are the disadvantages of DWC?

One drawback of DWC is that it provides a significant challenge for growers accustomed to soil-growing and have decided to try hydroponics. In comparison to soil growing, you’ll have to handle a more technically complex system.

In using the DWC technique, it will be helpful for you to save time constructing the setup by yourself. This store sells a ready-made dwc bucket. It is complete with everything you need to grow marijuana via deep water culture

4) Nutrient film technique

Any indoor growth system that adapts hydroponics principles can use the nutrient film approach (NFT). In a structural sense, the NFT method is similar to the ebb and flow method. Many growers will testify to the effectiveness of NFT when it comes to developing cannabis plants swiftly.

How does NFT work?

Instead of trays, cultivators employ a tube system with holes bored for the plants, mainly because it is easier to angle for proper flow over the roots. The nutritional solution is moved to the higher portion of the system by the pump, which uses shallow tubes that are slightly inclined. By gravity, the nourishing solution eventually travels to the bottom part.

What are the advantages of NFT?

For one thing, treating cannabis plants with the exact amount of nutrients they require at each stage of their development virtually guarantees superior outcomes. Cannabis grown via NFT almost usually outperforms cannabis grown by other methods in yield quantity and quality. You could end up with more high-quality bud than you know what to deal with, even if you have limited expertise and experience.

Furthermore, the NFT system has the potential to be both energy-efficient and environmentally friendly. The nutritional solution circulating is recycled multiple times, resulting in little to no waste. In addition, there is virtually minimal chance of run-off into the environment. The amount of energy required is small, and a sound NFT system can efficiently take care of itself.

An NFT configuration might also be surprisingly cost-effective to purchase and operate. The system and its components can be utilized endlessly for recurring grow-cycles once the initial purchase costs have been covered. In addition, advanced electronics can help growers to automate the great majority of their essential procedures.

What are the disadvantages of NFT?

The main disadvantage of the nutrition film technique is, of course, the exceptionally high learning curve for newbies. In addition, the nutrient film process is far more complicated than simply dropping a handful of seedlings into a pail of soil. You might also discover that you want a little more space in the first place, as well as access to a stable power source. 

What nutrients should I use for cannabis hydroponics?

You are responsible for delivering all of the nutrients required for plants to survive while grown hydroponically. The macronutrients nitrogen (N), phosphorus (P), and potassium (K) are the three major nutrients for plant growth. There are also secondary or also known as micronutrients that will aid the plant’s development. Boron, Calcium, Copper, Iron, Magnesium, Sulfur, and Zinc are some of these.

Many companies produce hydroponic nutrition solutions that are tailor-fit to specific growth phases. It would be best to use nitrogen-rich nutrient solutions in the vegetative stage, while phosphorus-rich nutrients will become more critical in the flowering stage.

Nutrients will be pre-mixed in a solution or delivered as powder. While powdered nutrients are less expensive and less bulky, if you are a first-time grower, liquid pre-mixed nutrients are preferable because they mix readily with water and are more manageable.

In order to determine the nutrients which your growth lacks, read my blog How to Know Which Nutrients Are Lacking in Cannabis Plants?

Can I grow organic crops via the hydroponics approach?

A clear definition of "organic" will settle this question. Based on the US Department of Agriculture a "produce can be called organic if it’s certified to have grown on soil that had no prohibited substances applied for three years before harvest." The critical term here, of course, would be "soil." Hence, hydroponics is not an organic way of producing crops.

According to the European Commission, which happens to be the official website of the European Union, organic farming is an agricultural method that aims to produce food using natural substances and processes.

It then expands the quality of organic farming as having a "limited environmental impact" that encourages many factors such as "enhancement of soil fertility." (Ibid.)

Once again, we read that the soil is an element for organic farming.

Considering USDA and EU law, it is not easy for hydroponics to qualify as a form of organic farming. Yet, this is still a debatable issue among growers who hold onto a broader meaning for organic.

For some, organic hydroponics is achievable by adopting the aquaponics approach.

What is aquaponics?

Another innovation in cannabis farming involves the inclusion of fish. Growers call this technique aquaponics. While hydroponics refers to growing marijuana plants with the absence of soil, you are introducing fish to the water in aquaponics. By so doing, they can attain organic hydroponics.

Cultivators raise fishes in a tank, and the nutrients they create (contained in their feces and produced by their gills) are transformed by bacteria into nutrients for the plants in a growing aquaponic system. The plant roots clean the water before being re-circulated back to the fish tank, completing the cycle.


Although aeroponics does not use any soil medium, it still does not qualify as a hydroponics setup. This is because, in hydroponics, the plants’ roots have direct contact with a nutrient-rich solution. On the other hand, plants are suspended in the air in aeroponics and with roots sprayed with a mist of nutritional solution.

In some setups, this scenario is likely. For example, you should produce a backup electricity source using deep water culture and nutrient film hydroponics techniques.

Checking the pH level of your solution is of utmost importance because this determines how effectively your plants will absorb their needed nutrients. Experts advise you to check the pH of your setup every three days or whenever you notice any symptoms of nutrient deficiency.

In maintaining your hydroponics reservoir, you should watch out for these factors: pH level, temperature, irrigation, and leaks. All of these contribute to the quality of harvest you would have, so really pay close attention to them.

Despite the absence of soil in hydroponics, plants are still susceptible to damaging insects. Some of these pests are fungus gnats, aphids, thrips, and spider mites.

A soilless grow medium is used in media-based hydroponics to help plant roots maintain the weight of a growing plant. Rockwool, coco coir, expanded clay, perlite, gravel, vermiculite, grow stones, and others are available for the media-based hydroponics system. In the end, the decision is based on personal preferences, budgets, availability, system design, and irrigation.

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