Hydroponics has always been best friends with cannabis plants. But what about hemp? Hemp is becoming more and more relevant as people are turning to different cannabinoids, such as CBD, rather than just growing for THC content. Naturally, hydroponics continues to be a grow method of choice.

Read on to learn all about how hemp hydroponics works!

What is Hemp Hydroponics?

Hemp hydroponics is the process of growing your hemp crop hydroponically. Hydroponics is a method of growing plants without using soil. There are many different hydroponic systems, which we will go over later on in this article.

Lots of commercial and home-grown hemp is grown hydroponically. This is partially because these grows may have to be indoors and private. 

Hemp hydroponics is popular for a reason, so hold onto your seat and let’s get started!

Top Benefits of Growing Hemp Hydroponically

Let’s talk about some of the top benefits of growing hemp hydroponically, including faster growth and larger, high quality yields.

Hemp Hydroponically

Faster Growth

One of the most sought-after benefits of growing hemp hydroponically is the rapid growth rate of your hemp plants.

Hydroponics is so effective because you control every aspect of your plants’ environment. Ranging from the temperature to the exact nutrient levels to the intensity of light, you can completely personalize your setup towards what hemp plants need.

When done correctly, this will result in a huge growth spurt and an increase of growth rate.

Larger and High Quality Yields

Likewise, a hydroponic system that’s dialed in correctly will result in larger, high-quality yields. With the exact nutrient, water, light, and temperature needs of your hemp plants met, they will thrive like you’ve never seen before.

Common Hemp Hydroponics Techniques You Can Try

Some common hemp hydroponics techniques you can try include: DWC, ebb and flow, RSS systems, aeroponics, and NFT.

Let’s talk about each technique in more depth!

Deep Water Culture (DWC)

Deep water culture systems is most likely what comes to mind for the majority of the population when they hear the word “hydroponics”. 

DWC utilizes a reservoir filled with mineral-rich water. Above the reservoir, there’s growing medium holding up the hemp. The hemp roots are suspended in the reservoir indefinitely, always in constant contact with the water.

But how come the plants don’t drown? Deep water culture systems use an air stone and an air pump to oxygenate the water and root systems. 

When you take a cutting of a plant and stick it in a glass of water to propagate roots, you’re creating a simple, small DWC hydroponic system.

Ebb and Flow

Ebb and flow hydroponic systems are also known as flood and drain systems. The terms are used interchangeably and refer to the exact same thing.

Ebb and flow systems consist of a grow tray and a water reservoir. The grow tray contains the substrate which holds your hemp plants in place. The water reservoir is filled with a mineral-rich solution.

Water is transported from the reservoir via a water pump and “floods” the growing tray periodically throughout the day. This process is automated by a timer which you can adjust for the specific needs of your hemp plants.

Finally, the water and nutrient solution drains down into the substrate to reach the roots. Over the course of a few hours it drains completely back into the reservoir, upon which the process repeats itself.

RSS Systems

RSS systems use pots filled with expanded clay balls- also know as LECA- which work as the substrate for your plants. The pots are all connected to an external water tank by pipes. The reservoir contains water and a nutrient solution.

Similar to ebb and flow hydroponic setups, RSS systems use an electric water pump and a timer to periodically flood the substrate with mineral-rich water. 

It should be noted that RSS systems are incredibly popular among the hemp-growing community.

Aeroponics

Aeroponics is typically reserved for commercial grows, although some dedicated home gardeners use aeroponics too.

Aeroponics involves suspending entire hemp plants in the air, keeping their roots exposed. A fine, pressurized, nutrient-rich mist is deployed throughout the day to keep the roots hydrated.

Aeroponics is one of the most resource-efficient hydroponics systems. On top of excellent resource usage, aeroponics produces huge yields while taking up little room. 

More can go wrong with aeroponics than in most other hydroponics systems because there are so many complicated moving parts. This is a large reason why it’s not the system of choice for most small-scale grows.

Nutrient Film Technique (NFT)

NFT hydroponics is a hydroponic method consisting of suspending your hemp’s roots in a thin film of flowing nutrient solution.

NFT is a collection of sloped tubes through which the water flows via gravity. The water collects in a reservoir at the bottom and is then pumped back up to the top. The plants are placed throughout the tubes with the roots dangling below to uptake nutrients.

Hydroponic cultivation technology for Hemp

Hydroponic systems have been used in traditional agriculture for quite some time now. Namely, leafy greens are well known for being grown hydroponically.

And although it’s a common technique for growing cannabis, it’s not as common for hemp. There are only a handful of commercial grows that use hydroponic technology to grow CBD strains.

Home growers of cannabis readily accepted hydroponics as a solution to increasing THC levels and the overall health of their plants.

But now that people are starting to become more and more interested in CBD, the same methods can be used to grow CBD-dominant strains of hemp. 

Passive Hydroponic Systems for Weed

Passive hydroponic systems for weed don’t require any external energy to work. Their low-tech designs are inexpensive, easy to set up, great for beginners, and won’t hurt your electricity bill!

The wick system and the Kratky method are both passive hydroponic systems.

Active Hydroponic Systems for Weed

Active hydroponic systems require an external energy input to work, such as electricity to power water pumps. They’re easily automated and are incredibly efficient.

Active hydroponic systems include DWC, ebb and flow, NFT, and aeroponics.

The Cost of Growing with Hydroponics

Hydroponic systems can cost between dozens and hundreds of dollars. Large systems are up to thousands and tens of thousands of dollars.

You also need to consider seeds, substrate, fertilizer, and- importantly- electricity. The power needed to keep the lights on- so to speak- will certainly increase your electricity bill.

Materials Needed to Make a DIY Hydroponic System

The materials needed to make a DIY hydroponic system to grow hemp depends on what hydroponic system you’re choosing to build. If you’re building it yourself, you will likely want to create an RSS system.

To DIY an RSS hydroponic system to grow hemp, you will need: pots, PVC pipes, expanded clay balls (LECA), a water pump, and a timer. Plus your hemp plants of course!

Choose a Growing Medium to Get Things Started

Let’s go over some different growing mediums you can choose from to get things started!

Perlite

You may already be familiar with perlite, as it’s often found in potting soil. It’s a volcanic mineral that is put under intense pressure until it pops into small lightweight, porous globes.

Perlite is great for aeration and quick drainage, but isn’t a good option if you’re looking to increase moisture retention. It’s the medium of choice for wick systems and is often used when growing potatoes.

Coco Coir

Coco coir is made from the husks of coconut shells. It’s completely organic and environmentally friendly since it’s a byproduct of coconut production.

It’s great for water retention without staying overly damp. That being said, it’s best mixed with other mediums to increase drainage.

Expanded Clay Pellets or LECA

Expanded clay pellets are also known as LECA (lightweight expanded clay aggregate). LECA is created by heating clay until it expands and becomes porous.

LECA drains incredibly quickly, so it has to be used strategically.

As mentioned earlier, RSS systems- one of the most popular growing methods for hemp- utilize LECA.

FAQs

Now let’s answer some common questions about growing hemp hydroponically.

Can you grow hemp hydroponically?

You can grow hemp hydroponically. Hydroponics is the grow method of choice for many home growers of cannabis. As CBD-dominant strains slowly take the main stage, more and more hemp is being grown hydroponically too!

How many gallons of water does a hemp plant need?

Hemp plants need about 6 gallons of water each day when being grown in a traditional soil garden or farm. On the other hand, hydroponic systems are constantly recycling their water. While hemp plants may require 6 gallons of water per day, in a hydroponic system that can translate to one gallon recycled six times.

Is Growing hemp indoors profitable?

Whether or not growing hemp indoors is profitable depends on many factors. On the one hand, it can be more expensive to operate a hydroponic grow setup compared to growing in a traditional setting. 

That being said, you will end up with a larger yield and be able to produce more hemp per square foot when growing hemp using an indoor hydroponic system. This means you’ll have more hemp to sell.

At the end of the day, it depends on how much hemp you’re selling and how much you’re charging for it.

How much is an acre of hemp worth?

An acre of hemp is worth about $300. You can grow much more hemp with an acre of hydroponics than you can with an acre of a soil-based farm.

Is it better to grow hemp indoors or a greenhouse?

Generally speaking, it’s better for small operations to grow hemp indoors. You’ll have better control over the growing environment and your hemp plants will be less susceptible to pests, diseases, and mold growth.

Can you grow hemp in a container?

You can grow hemp in a container. Use a very large pot- hemp plants can grow to be extremely tall! This height will require an extensive root system with lots of room to spread out. Your hemp plant may benefit from a cage or stake to help keep it upright.

Is Growing hemp with hydroponics water intensive?

Growing hemp with hydroponics is less water intensive than industrial hemp systems using soil. Water gets recycled in hydroponic systems so the resource is used to its full capacity.

Conclusion

Hydroponic hemp is the way of the future! There’s a reason why hemp growers are happy to adopt this method of growing. As the CBD market and demand of hemp expands more and more, we’re likely to see a big boom in hydroponic hemp grows.

Check out the rest of our blog for more interesting hydroponic guides!