How Vertical Cannabis Growing Works

Now, you may be comfortable with standard cannabis growing, but you can only achieve so much with traditional techniques. You may think the most you can change is whether you apply training methods or grow in a SOG, but vertical growing will have you shifting the process, quite literally, from the ground up.

We’ll show you what it is and how it stacks up to the standard method, along with exactly how a vertical grow comes together.

What Is Vertical Farming?

To define vertical farming (or vertical growing), we first have to define horizontal growing. The latter is what most cannabis growers do, setting up plants on the same plot of ground with nothing but the light above them. Vertical growing, in contrast, takes advantage of the space above by allowing additional plants to grow on top of the initial plot.

By taking advantage of this extra space, vertical growers are able to net double or more their usual yields.

How Does Vertical Cannabis Growing Work?

“But wait”, you might wonder, “How would a cannabis plant be able to grow on top of another plant?”. Well, there are a couple of ways it’s done. One method is a modification of horizontal growing, while the other is considered a more difficult yet “true” vertical farming method. These are known as rack and tower setups, respectively, and you’ll soon find that their names explain their nature.

Rack Setup

Starting off, a rack setup is essentially when you use shelves to create second, third, etc. horizontal grows above each other.

Naturally, since you’ll have whole plants directly on top of one another, you can’t grow like this outside. In turn, you’ll need to consider indoor lighting very thoughtfully. Instead of having the light source positioned above, however, you’ll have your stack set up next to a long tubular light that shines on all of your plants. If you have multiple stacks, you can set them up around the light tube so they’re all evenly exposed.

Since it’s just racks of horizontal grows, feel free to use soil as your growing medium. However, if you want to try a hydroponic system, such as the nutrient film technique, that’s also a popular choice.

Tower Setup

Sure, rack setups take advantage of unused space, but tower setups are as vertical as growing gets. See, instead of sitting in individual pots, all of your plants grow out of openings in the side of a hollow cylindrical tower. If your tower is big enough, this system allows you to grow more than a dozen plants in a space where you’d normally only be able to fit one or two at most.

As with the rack setup, you’ll also have lights propped up on the sides of your tower to ensure even light exposure. That is, of course, if you’re indoors. With tower setups, though, unlike racks, you also have the option of growing outdoors.

Tower setups also differ in terms of the specific growing system they allow for. Rather than growing into soil or water, the roots sit suspended in the air in what’s known as an aeroponic system. You’ll feed them by misting water and nutrients into the tower, resulting in the most efficient possible delivery of both.

Regular Cannabis Growing vs Vertical Cannabis Growing

We’ve been mentioning some interesting perks of vertical farming, but do those benefits really make it better than the tried and true horizontal approach? Well, it depends on what type of grower you are. Let’s break down the advantages and disadvantages of both.

Regular Cannabis Growing

As mentioned before, cannabis is regularly grown in a horizontal system, where plants are placed next to each other, not above or below. This is how most plants have always been grown, so there’s nothing wrong being done here.

Pros:

• Simplicity: This is the most straightforward method of cannabis cultivation, and is therefore the best method for beginners.

• Cheap: Since this method also requires less equipment, the financial burden won’t be nearly as intense.

• Less labour: No additional setup is needed, apart from getting your grow room or outdoor space together, so this method is also good for those looking to cut out extra labour.

Cons:

• Inefficient: Relative to the amount of ground space it takes up, regular cannabis cultivation is inefficient compared to vertical alternatives. You’re only able to put one or two plants on a plot of ground that, as we explained, could hold up to more than a dozen. Along with that, the traditional way of giving plants water and nutrients leads to waste in both regards.

• Limited: In turn, since you’re limited to fewer plants, your total yield per harvest will also be limited. It may not be a problem at first, but it becomes more of an issue when you want to expand your operation.

Vertical Cannabis Growing

So, you may have known about those aspects already, but how does the horizontal method stack up in comparison to a vertical cannabis grow?

Pros:

• Efficient: A vertical grow allows you to take advantage of the space above a cannabis plant. Instead of one or two plants in a given space, it may be six, eight, or more than a dozen! In addition, if you grow in a tower setup, being able to mist nutrients and water onto the roots is far more efficient than the standard method.

• Better results: Since you get to have far more plants in a given space, you’ll end up with higher yields per square metre in turn.

• Potential for additional crop cycle: Along with all that, since the vegetative stage is often shortened, you may have the chance to get another vertical crop cycle going in the same year.

Cons:

• Expense: Naturally, the other plants won’t grow vertically by themselves, so you’ll have to make a bit of an investment before you start. The price tag won’t be too high if you utilise the rack method, but a good tower system and the necessary lighting could run you around €1,000 or more.

• Maintenance: As you grow more plants in your usual space, you’ll have to get more/stronger equipment, such as fans, air filters, dehumidifiers, etc. You’ll also want to get more temperature sensors to account for the difference in how your upper-level plants feel versus the ones below.

• Potential risk: Lastly, as you may have to use a ladder to access plants towards the top of the system, you have to consider the potential physical risk that comes along with this.

How to Make a Vertical Farming Setup for Cannabis

Now that you have a clear idea of the process, you’re ready to start assembling your very own vertical grow!

We’ll be focussing on the rack setup for this walkthrough, as building a growing tower is only possible for those with lots of work space, equipment, and tools on hand. A rack may not be as efficient as a tower, but it gets very close relative to the time, money, and effort you’ll save in the process.

Step 1: Set Up Your Cannabis Growing Rack

Rather than just getting a standard rack from a gardening or office supply store, you’ll want to look for racks specially made for growing cannabis plants, or plants with similar demands. Simply enough, this is because they’ll be equipped to house lights for your plants, and they’ll be sturdy enough to hold all that cannabis at once.

They come in all sizes, so be sure to pick one that will fit in your grow room, with extra space all around. Rolling racks are ideal for optimising space, but stationary ones work too.

Step 2: Pick a Strain That Will Thrive

Considering just how tall certain cannabis plants can get, not just any strain will work in a vertical setup. Really, you just have to ensure your plant’s maximum height doesn’t get too close to, or exceed, the available space. Autoflowering strains could be perfect here, but you can also find photoperiod strains that either end up short or can be trained into staying petite.

Step 3: Pick Your Grow Lights

While you’d usually throw a sizable lamp up on the ceiling and call it a day, growing vertically on a rack calls for an intricate network of lights situated much closer to the plants than usual. In turn, LED lights are more of a requirement than a suggestion. You can pick either white or purple (broad or targeted spectrum) lights, but just be sure your lights match to ensure optimal growth.

Step 4: Prepare Your Environment

You’re sticking far more plants than usual in your grow space, and will need to prepare your environmental control system in turn.

To start, you’ll want to automate whatever systems you can. You have a lot more plants to look after, so automatic alerts of their condition will save you tons of effort. From there, be prepared to cool down your system if the crowded rack warms up the room. Concerning airflow, you should facilitate air being pushed down from the rack's open areas and pulled out from the other end.

Step 5: Decide How Your Plants Will Grow

With all that in order, the rest of your growing journey comes down to what specific growing methods you implement from here. Will you train your plants to stay at the ideal height of a metre or below? Grow them in little seas of green? It’s all up to you. Just keep in mind that, given their stature, your plants will not spend as much time in the vegetative stage as normal plants. This process, accordingly, is what allows for a potential second grow cycle in one year.

What Else Do You Need to Know About Vertical Cannabis Farming?

The above steps should cover all the basics of setting up a vertical grow using a rack system, but that’s not all there is to keep in mind. Here are some additional tips to consider.

Keep Everything Clean

Since you’ll have a whole new piece of large equipment in your grow room, which is also the surface your plants sit upon, you’ll want to make sure you keep it clean. Whether it’s soil, dust, or anything else that ends up on your rack or in the room, clean it up quick.

Since you have a lot of plants growing together in the same space, there’s that much more potential damage if diseases or mould end up getting to your plants.

Shift Light Schedule Earlier

Along with that, you’ll also want to stay focused and remember to adjust the light schedule for all your lights when necessary.

This will be required much sooner than it would be for plants growing regularly, as short plants don’t need as much time in the vegetative stage. As a result, promptly shifting your plants from the vegetative to flowering stage via light adjustment is key for maximising yields.

Consider Your Budget

Last, but perhaps most important of all, you need to consider your budget before diving into any of this. Yes, maybe you can afford the rack, plants, lights, etc., but are you remembering to account for the nutrients and water you’ll have to use? How about the energy bill? Many expenses you face in a regular indoor grow could cost double or more in a vertical system.

Now, that’s offset by the fact that you’re obtaining far more buds than you would normally, but not many can afford to wait for that delayed return on investment. Don’t risk too much, and be financially realistic with yourself before you start cultivating more cannabis plants.

Is Vertical Cannabis Growing the Future?

So, considering how it saves space and allows for more plants to be grown, is vertical cannabis farming the future? Well, since not every cannabis grower can afford it, or be bothered to shift from the more proven method, it won’t completely replace the standard. That being said, as the technology is perfected and becomes more affordable, you will see far more cannabis growers working vertically.

Adam Parsons

Professional cannabis journalist, copywriter, and author Adam Parsons is a long-time staff member of Zamnesia. Tasked with covering a wide range of topics from CBD to psychedelics and everything in between, Adam creates blog posts, guides, and explores an ever-growing range of products.

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