Why This Vertical Farm is 500x More Efficient Than Farming

This is Vertical Harvest. Sitting on half an acre of land, it produces as much food as an equivalent 250-acre farm. That’s a 500 times more efficient use of land than traditional farming. But if vertical farming is so great, why isn’t it more popular? And where and why does it make the most sense?

So come with me as we tour one of Americas newest and most advanced Vertical Farming setups in a facility just outside Portland Maine. We brought our cameras to capture everything … and found out that vertical farming is a lot more complicated than just “plants on shelves,” and a lot more interesting too.

To say that I was excited to get inside a vertical farming facility would be an understatement. I’ve always been fascinated behind the engineering and logistics for how they work. And we’ll be getting into all of that, but first I met up with Chris Hogberg, the General Manager of the Westbrook facility, and he gave me a quick rundown before we got into the seeding, growing, and harvesting process.

Facility Overview

“We do really want to bring the farm experience to the public. So as you’re in here, you’ll see trays moving above you on this conveyor belt. And then trays getting ready to be harvested, moving above you on this conveyor belt. So the plants will literally be hovering right above you.” – Chris Hogberg

“So people will be in here trying it out and they’ll be seeing all the food growing.” – Matt Ferrell

“And they’ll be seeing it grow.” – Chris Hogberg

“Yeah, it’s really cool.” – Matt Ferrell

“Also, of course, the big picture window, so you can see, and this is really the heart of the processing room right after the harvesting machine, the glass facade. Many people think that is for the plants. It is not. We don’t use any natural light to grow our plants. It’s all LED light. At our farm in Jackson we did use a lot of the south-facing windows to grow plants but it introduces variability in the climate. So you know we are a CEA controlled environment agriculture farm and the E is really important. The environment is super important in what we do.” – Chris Hogberg

That last part is a big deal. At their original pilot farm in Jackson, Wyoming, they used south-facing windows to help grow produce. But sunlight introduces problems. The sun heats one side of a building more than the other. Concrete walls absorb heat unevenly. Little microclimates form on the growing floor, leading some plants to grow faster than others. That’s a problem when you’re trying to grow a consistent product across thousands of trays. So here in Westbrook, every photon hitting those plants comes from LEDs. These lights are one critical piece of a massive system that keeps the ideal growth environment locked in, floor to floor, rack to rack. That control creates dependability, and begins to explain why vertical farm setups like this one make a lot of sense.

But exactly how much food are we talking about?

“This plot of land that we’re sitting on is comparatively quite small. It’s a half an acre plot. But we’re able to pack a lot of growing capacity into this because we’re: A) using hydroponics, B) going up. We can grow 365 days a year, 24 hours a day. We’re able to pump out a lot of volume to the tune of around 3.5 million pounds of produce. And that number varies because if we grew all pea shoots, we could grow a lot more. If we all grew only French sorrel, we’d grow a lot less.” – Chris Hogberg

3.5 million pounds is huge! The average American consumes just 155 pounds of vegetables a year. That means one of these farms could potentially provide produce for tens of thousands. ¹

Vertical farms are in the salad business, they only grow greens here. No fruits. No root vegetables.

It’s the same across the industry, where leafy greens, herbs, and microgreens predominate along with lettuce, kale, basil, arugula, and bok choy. The reason is simple: Salad greens make salad dollars. These crops grow fast, they’re lightweight, they’re high value, and they don’t need a lot of vertical space per plant.^{2 3}

Staple crops like wheat, corn, and rice need way more room and just aren’t economically viable in a setup like this. Some farms are experimenting with crops like strawberries and tomatoes, at a larger scale. But for now, leafy greens are where the math maths out.

And Vertical Harvest is actually a bit more flexible than most. Arik Griffin, their Chief of Farm Systems, told me their trays were designed to be adaptable. They have plastic toppers that let them grow head lettuce, herbs, and other products beyond microgreens. A lot of farms are purpose-built for one specific crop. Vertical Harvest chose to trade perfect efficiency for being able to grow a wider variety of greens.

And there are some interesting details about those custom trays and the logistics of getting them here … but we’ll get to that later. First, Chris wanted to show me how this place actually works. And it starts on the ground floor with seeding.

Seeding

“We’ll just run straight back.” – Chris Hogberg

“So this is germination prep, also known as seeding. What we have here is a radish blend of seeds that we pour into the hopper here on top. And it will drop into the feeding area and when we turn on the vacuum it’ll get it right into place, so let’s get it started. All right so here’s our handy dandy any directional screen. What we do is we have our seed dispenser on for our one seeding drum. We’re going to turn on the vacuum here. It gets a little loud. I’m gonna have a second and then we’ll press this one. We’ll pull the seeds on. So you’ll see that once it goes through the seeder, it’ll continue down the line.” – Lindsay Lymer

“How do they suck to it?” – Matt Ferrell

“So that is all vacuum. It has these tubes inside. In fact, I’ll show you another empty drum. So what you’ll see is that the vacuum will pull the air through these tubes here. And will actually suck the seed onto the tiny little holes. And each of these holes and patterns are different between the types of species that we’re receiving.” – Lindsay Lymer

“Oh, I see like bok choy, kale, you have different…” – Matt Ferrell

“Exactly. So right now, the one that we have missing is our radish drum.” – Lindsay Lymer

“Okay, so we’re seeing radishes.” – Matt Ferrell

“We’re receiving radish blend, yes. So you’ll see each drum has different whole sizes as well as amounts and things like that, as well as multiple drum units. So because of today’s recipe we’re going to be using only one of our drums and we’ve got everything ramped up and ready to go.” – Lindsay Lymer

“It’s watering over here? Yeah. I just want to peek in just myself.” – Matt Ferrell

Okay, so I thought that was fascinating. After the drums finish seeding the trays, they get an initial spray of water. From there, they continue on to the germination room. But before we peek in there, I want to set expectations. When I visited, they were just starting to ramp up production. So what you’re about to see is only a fraction of what these rooms will eventually handle.

“And then real quick, as we go in here, this is our germination room. It’s not currently in use for germination. But it gives you an idea of how the racks work upstairs, and we’ll get into that a little bit more upstairs. The trays have two options. They can go on the lower conveyor belt or the upper one. If they go in the lower conveyor belt, they go into this and get pushed into this rack. So if you think of this in action, you have trays that have just been seeded. Yeah. They move into this system and then you have trays on one of these levels that have been here germinating for three days. They’re ready to go upstairs. That seeded tray pushes in to the germination chamber while pushing out one of those trays that has been germinated so it can go upstairs.” – Chris Hogberg

“Okay.” – Matt Ferrell

“6,000 trays can fit in this room. Because they’re germinating, we can stack them really tightly.” – Chris Hogberg

From the germination room, it was time to head upstairs to the grow rooms. There are two of them. One on the second floor, one on the third. And they are massive. The first thing you’re going to notice is the pink light. There’s a reason for that, and I’ll explain it in a bit. But first, let’s just get in there.

Grow Rooms

“I’ll just take you out of this door.” – Chris Hogberg

“Oh, wild.” – Matt Ferrell

“Into the grow room. Oh, my gosh. Woo! So right now, on the second floor, we’re currently only growing on two of these racks. This is so tricky.” – Chris Hogberg

“That is so cool. This is huge.” – Matt Ferrell

“And we did just bring quite a bit of produce down for harvest, but you can see these were seeded two days ago. These ones, yeah, two days ago, you can already see them starting to sprout. You can’t really see the produce growing on the upper racks right now.” – Chris Hogberg

Even with just a fraction of the racks in use, the scale of this place was … massive. Rows and rows of shelving stretching across the entire floor. And all of it glowing pink.

So about that pink light. Plants care about which photons drive photosynthesis. They don’t need the full spectrum of visible light that you and I see. Plants love red and blue light⁴, but they don’t care much for green light. They reflect it back, which is why leaves look green to us. So there’s no point wasting energy on wavelengths the plants don’t care about. Red LEDs are cheap to run and deliver exactly what plants need to grow. They make up the bulk of what you’re seeing in here. But there is some blue mixed in too. That’s what gives every vertical farm that signature pink glow.

But this mixture of lights isn’t just about setting the mood, it’s about setting the conditions for a bumper crop and a sustainable business. The right mixture of red and blue lights can enhance the growth and nutritiousness of greens, but can’t break the bank. ¹ Blue LEDs are expensive to run, so the recipe leans heavily red. This isn’t a trivial issue. When lighting is your single biggest operating cost, choosing the most efficient wavelengths isn’t optional. It’s economic survival. Energy consumption is the biggest challenge the industry has faced. You might say it’s the main reason it hasn’t yet taken root. ⁵

To grow and thrive, plants need the right light and temperature. Outdoors the sun and the earth do that work … for free. Indoors it’s done by a LED lights and a powerful HVAC system. They use the most efficient tech possible, and even have the systems work together: the heat generated by the LEDs is recaptured to help drive the HVAC system.

Now about those energy intensive lights. There are 42,000 individual lights in this building. Dedicated lights for every tray. That’s deliberate. If one tray gets more light than the tray next to it, you get uneven growth. So every tray gets its own fixture.

I spent time with Arik Griffin, who designed the automation and growing systems for this facility. As we walked through, you probably noticed all the tiny tubes looping at the base of each rack. That’s the irrigation system. It drips nutrient water into the base of each tray, and the trays are gently sloped so water drains out the other side. Pretty simple.

But the airflow system is what really surprised me.

“Airflow is pretty important for growing plants. They need the air to be moving along, and they need it to be pretty uniform. What you don’t want is really high airflow on one spot and no airflow on another spot. Right? You get that uneven growth that I was talking about. So, if you ever played air hockey as a kid, you are familiar with the holes in the air hockey table. It creates a uniform cushion of air for your puck to flow down. So what we did was we took that concept and this entire system here is a wall of airflow that pushes out this way. We’ve got big air handling units that drive air into these channels and drives it out all of those individual holes. So we’re able to just deliver a wall of air that is coming out and providing physical airflow as well as delivery of the right temperature, turnover, as well as supplementation of CO2.” – Arik Griffin

Now, here’s something that honestly hadn’t occurred to me until I was standing in the grow room. When you seal up a building like this and fill it with thousands of plants, they’re going to eat through the CO2 in the air. Fast. Outdoors that’s not a problem, but in a sealed environment like this you have to pump it in. And the numbers are kind of wild.

“CO2 supplementation is required in this building. If I were to fill this building with plants and not supplement it with CO2, the CO2 in the ambient air would go to nothing like that and the plants would stop growing. There’s no physical way for us to get enough outside air at the right temperature into this building in order to supply enough CO2 to the plants without supplementation. So we have to. And we go through about a little less than 30 tons of CO2 a month.” – Arik Griffin

“Wow. That’s a lot.” – Matt Ferrell

“The plants eat it all.” – Arik Griffin

Remember the germination room downstairs? How one tray pushes in and another tray pushes out? The grow rooms work on the same principle. Just way bigger. Elevators carry trays up to the right level, push them into a rack, and when a tray is ready for harvest, a new one takes its place and the mature tray gets sent back downstairs. Some crops take as little as a few days, others a few weeks. The whole building is basically one giant loop.

“The trays come from that end. They get pushed here, they get picked up by the elevator, brought up to the next level and shoved forward. So it’s just a constant, it’s a big rotation. Yeah, so when it’s ready to go, they get pushed out here, taken out the conveyor, sent downstairs on that rotating pattern elevator into the harvest room.” – Arik Griffin

Remember those custom trays I mentioned earlier? There are 42,000 of them needed for this building. Each one has an embedded RFID tag to track its location through the entire system. And about 90% of the equipment in this facility was shipped from the Netherlands.

“Right now we only have a limited number of these trays physically in the building. There’s another shipment of these trays on a boat right now, steaming our way. As soon as they arrive, we will load them in and start ramping up capacity. We’ve got about 2,000 trays, I’m sorry, 3,000 trays every two weeks. And so it just takes time to fill the building and load them up with products.” – Arik Griffin

“So the current holdup is just waiting on trays.” – Matt Ferrell

“Yeah.” – Arik Griffin

“That’s got to be irritating.” – Matt Ferrell

“What it’s allowing us to do is run the system through its cases. Any automated system is going to have little adjustments that need to be made. We’re finding all of those. We’re making those adjustments now so that when the big batch of trays shows up, we’re ready to run them through smoothly without a lot of interruptions.” – Arik Griffin

Before we left the grow room, Arik pointed out that the lights were only running at a fraction of their full output. No point blasting them at full power when most of the racks are still empty. But he offered to crank them up to a hundred percent just so we could see what it would be like at full capacity. It was … bright.

“We’re gonna go all the way to a hundred just for a moment. Yeah, cuz it’s expensive and blinding probably and somewhat blinding. All right, here we go … ready?” – Arik Griffin

“Okay, yeah” – Matt Ferrell

“Yeah, it gets a little unpleasant And your vision is going to be really funny after this too.” – Arik Griffin

He wasn’t kidding. When we walked into the stairwell to head back down to the harvest floor, everything looked green. Like, everything. I have to say, seeing the world through spinach-vision was a little disconcerting. After a few seconds I’d had more than my chloroFILL of it.

The first thing I noticed on the harvest floor was the temperature. It was cold. Like standing inside your refrigerator cold. That’s deliberate. The produce gets chilled the moment it’s harvested and stays cold from that point on. Because Vertical Harvest delivers locally, that cold chain is short. The greens go from this building head straight to a store shelf within the surrounding community. That means their product can stay fresh for weeks longer than the same crop shipped in from across the country.

The trays ride an elevator down from the grow rooms. From there they move along a set of tracks and get fed through cutting blades that harvest the greens. The cut product drops onto a conveyor. It slowly works its way down the line to a collection bin. A worker sorts through the bin and passes it along to the next step.

From the collection bins, the greens move to packaging. Individual containers get filled and fed into a sealing machine. It covers each one, seals it. The way this sealing machine works, and the sound it makes, I have watched that step for quite some time. …I love this sound.

Then the sealed produce runs through a quality check for anything that shouldn’t be there. After that, each package gets stamped with a date and the name of the customer it’s heading to. And yes, they stamped this batch “Undecided.” I’m not going to lie, that made my day.

Safety

Now before I talked about how a vertical farm is a closed loop. The farm is like a huge biomechanical creature that eats energy and poops salad. To get these greens out, a very specific set of ingredients, conditions, and processes have to go in. And anything that could throw the system out of balance is not just a problem, but a threat.

So everything in this building has to be not just clean, but sanitized. If a pathogen or contaminant gets in, it can spread fast and wipe out an entire crop. Or worse, make people sick. Vertical Harvest takes this seriously.

Before we even stepped into the grow rooms, we had to put on protective gear and run our hands through a hand washing machine. I didn’t know that was a thing. It sanitizes and dries your hands automatically so you’re not touching anything before gloving up. Arik and the team are testing constantly to make sure surfaces and crops stay clean. I’ll get into that in a bit, but first, a key part of keeping everything safe is the water treatment and HVAC system.

“Okay, so water treatment room, this side of the room is all of our nutrient dosing. These are different, these are tanks with different nutrient concentrations and then things to adjust pH either up or down for the plants. These skids that you see behind us are constantly turning over those tanks that Chris was talking about. So we’re always making sure that those tanks are at the correct dosage as they’re being turned over. The skids over on this side are all of our water filtration. So you can see UV reactors there. All the water goes through a 50 micron mesh screen before passing through those UV reactors. Those are constantly being cleaned. If we see the UV transmission level go to a certain point, it’ll shut down, do a flush with acid to clean off any biofilm buildup, direct that water to the sewer, and start it up again so you have the correct transmission levels to kill all the nasties in the water. HVAC room. Also spent some some more time up here with Chris and Eric. Can’t tell, we had to build this whole greenhouse on a computer before actually building it in the field. This is very densely packed. – This is why, because of the spaghetti upstairs. Packed a lot into a small space.” – Chris Hogberg

“No kidding. Oh my gosh. This is a very densely packed mechanical room here.” – Matt Ferrell

That water treatment and HVAC systems provide the backbone for the whole operation. The water gets filtered through a 50 micron screen, hit with UV to kill anything growing in it, and then the nutrients and pH get dialed in before it goes back to the plants. They recycle about 95% of it. And the HVAC side is just as critical. Those 42,000 LEDs generate heat. The HVAC system recaptures that heat and uses it to regulate the building’s climate. On warm days, Arik actually dials the lights down because the building doesn’t need as much.

This entire facility is a carefully designed closed system, and because it’s a closed system they also have to be very careful of disease. They have to keep everything extremely clean … It’s all connected. But keeping the water clean and the air moving is only part of it. They need to be certain their facilities are bug free. Arik showed me how they handle that.

“After biological testing, I’ll incubate in this little incubator. After everything’s been incubated and I’ve tested everything’s clear, I put it all in a little kill bucket to make sure that there’s no contamination. This is an example of the swabs that we use. Basically, it’s just a little simple swab. We will swab a surface, and then we will pop this little reagent fluid, dump it down into the swab sample, shake it up. I’ll put it in that device and it will test and say, is this clean or is it not clean. And the same device can be used for microbiological testing.” – Arik Griffin

So we’ve talked about the LEDs, the airflow, the HVAC, and the water treatment. All of it running around the clock across multiple floors. And that brings up probably the biggest question hanging over vertical farming. Energy. This is a 1.5 megawatt facility. That’s a lot of power. And the vast majority of it goes to those lights. Like we mentioned earlier, power has been a challenge for vertical farming systems. I asked Arik about it and one thing I thought was clever is how they actually work with the local power grid instead of just drawing from it.

“But one of the things that we do is we actually cycle the lights down to react to peak demand charges. So the local utility, central main power, they have a window in the day when peak demand charges are high. And so we turn off the lights during those peak demand charge times, which helps us save on energy costs. But as I said, since this is a 1.5 megawatt facility, it helps reduce the load on the grid when the rest of the people in the community actually need that energy. And so we will ramp things back up at night to take advantage of when costs are low and when demand on the grid is low too.” – Arik Griffin

So after spending the day walking through this facility, where does vertical farming actually make sense? I think the answer is pretty clear. It makes sense where traditional farming doesn’t. In dense urban areas. In climates where growing seasons are short or unpredictable. In places where the supply chain for fresh produce is long and fragile. Vertical Harvest isn’t trying to replace traditional farms. They’re filling a gap. A half acre next to a parking garage, producing millions of pounds of fresh greens year round and delivering them locally. That’s a hard value proposition to argue with. Unless you really hate salad.

There’s something else about Vertical Harvest that I think deserves attention. About 40% of their employees have a disability. That’s not an accident. It’s part of their mission. The facility was designed with that in mind, and it’s something I came away genuinely impressed by.

Now, Vertical Harvest is still in its early days. They’re waiting on trays, fine-tuning the automation, and ramping up to full capacity. So the real test is what this place looks like six months from now, but what I saw was impressive. The engineering, the thought behind every system, the way it all connects. It’s a lot more than plants on shelves. They’re growing the future in here, and that future looks blindingly pink, and leafy green.

I want to thank Chris, Arik, Justin, Lindsay and the entire Vertical Harvest team for being so open and welcoming. They gave us full access and answered every question I threw at them. And a huge thank you to Nick, one of my Patrons, who connected me with Vertical Harvest in the first place and was behind the camera for this entire visit. I really appreciate it.