Darragh McCullough: Vertical Farming Is All The Rage, But The Downsides Will Limit Its Potential
What grows up, must come down: Vertical farming presents interesting possibilities, but it has its limits
Darragh McCullough
February 20, 2020
Vertical farming is all the rage. It makes great click-bait by combining key buzz words: 'technology' in the form of new LED lighting; 'novelty' food that some celebrity chef can shout about producing beside their New York restaurant, and 'sustainability' courtesy of zero food miles and a low carbon footprint.
Your phone's news feed is probably similar to my own.
There are so many stories about this tech that you would be forgiven for thinking that there is going to be a vertical farm at every traffic light next time you make it into the city.
But beyond the low-energy LED lights in colours tailored to turbo-charge plant growth even in the depths of winter, you realise that we've had vertical farms for decades.
More recently, I've seen production in tunnels and glass take on vertical formats. Modern glasshouses are now so tall that each line of tomatoes or peppers is tended to via nifty little scissor lifts. I see the same trend in tunnels, with 4m high tunnels now standard in new soft fruit set-ups.
When I visited the Farmony vertical farm in Ballycoolin, west Dublin for Ear to the Ground this year, we all had to gown up before being allowed access to the growing unit.
It might have appeared a bit over-the-top given that we were just stepping into a converted refrigerated truck container that has a few pumps, fans and extra sockets fitted.
But by manipulating every single aspect of this growing environment - and maintaining near-sterile conditions - the people behind Farmony claim that their 80 square metre unit can produce the same amount as a 5ac field. That's a 250-fold increase in the productivity per square metre, which is impressive by any measure.
Farmony is focusing on the unit's ability to grow leafy salads and herbs, especially the baby and micro-leaved versions that are so beloved of chefs and foodies.
Normally these are flown in from places like Africa, Israel and further afield at this time of year when it's just impossible to grow them commercially here in tunnels or glass.
The beauty about using refrigerated truck containers is that they are insulated, allowing the grower to maintain ideal temperatures at a relatively low cost.
They are also pretty secure and mobile so that they can be parked anywhere there's room for a truck container.
The idea is that they'll pop up in carparks, basements, and office block roofs, regardless of whether that's in baltic Belfast or boiling Beirut.
Farmony claims that the €87,000 price tag is a snip given that the herbs the container is capable of producing would pay that off after all costs in about two years.
The downsides? The unit should be able to work well for produce that is 95pc water and has a short growth cycle of just 1-3 weeks. These plants don't need a lot of heat and light to get to a saleable point. But if you wanted to grow a more carbohydrate-dense food - like any root crop, or even a strawberry where only a small fraction of the plant that you've poured light and heat energy into ends up being saleable - the calculations start to unravel.
And, much and all as we should be reducing our calorie intake, there's only so much salad that a body can take.
We'll certainly see more of the LED light tech being incorporated into existing production systems like tunnels and glass, and there are interesting possibilities for old mushroom tunnels to be repurposed as salad units.
But there's a lot to be said still for good old-fashioned horizontal farming.
Indo Farming