There are lots of imaginative concepts for skyscraper farms on the internet, towering glasshouses full of optimism and basil. Most of it is science fiction, but there are some interesting experiments out there that suggest urban farming may have a real contribution to make.
Work has just begun on what will be the world’s largest indoor vertical farm, taking over an old steel works in New Jersey. Aerofarms, the company behind the scheme, will need $39 million to build it, so it’s no small undertaking. The fact that Goldman Sachs have funded it suggests that it should be taken entirely seriously as a business.
What’s the point of urban indoor vertical farming? First, like any urban farming, food is produced where it is needed. That means fresher produce, less wastage from transport and storage, and fewer emissions. You can do all of that on an old fashioned market garden of course, so it’s the indoor and the vertical bit that are attracting the attention.
By growing indoors, Aerofarms can create the perfect growing conditions for their crops, regardless of seasons and weather. That means harvests all year round – up to 30 a year for the spinach and greens they’re going to be working with initially. These crops are speedy enough in a field, ready in 30 or 40 days. That can be shortened to 16 days under optimal conditions.
That speed has a couple of massive advantages. First, it means you can produce a whole lot more food in the same space – 70 times as much as you’d get if you knocked the steel mill buildings down and planted the land with traditional farms. You also undercut the 21-day life cycle of some of the key pests, meaning you don’t need any pesticides. The leaves have been harvested and eaten before the bugs can hatch and get stuck in.
A reduction in pesticide use is one of several important environmental benefits. The technique uses 95% less water, and there is no run-off or water contamination. Soil stewardship is another benefit, as Aerofarms don’t actually use any soil. The plants are embedded in a cloth medium, with their roots fed with a nutrient mist.
You might also notice that if you’ve grown your crops in mist and used no pesticides, you’re not going to need to wash these leaves much either. Aerofarms say that by picking leaves clean and dry, they can extend the shelf life of the greens, which reduces food waste at the retail and domestic end of things too.
I suppose, like a less extreme version of the synthetic beefburger, that some people will feel that a chain of authenticity has been broken here. That this clean and precise vision of dirt-free agriculture breaks our connection with the land, one step further in our delusion that we are somehow separate from the earth. I can see that, but I write this with dirt under my fingernails from the allotment, and I don’t see why we can’t have both.
More of us live in cities now than in the country, so increasing food production in and around our cities is a big opportunity. This is one of the areas where I agree with the eco-modernists. If we can do that while continuing to grow our own, teaching children to grow food, and encouraging the old style urban farming too, then everybody wins. I also suspect that a lot of things that we like to eat can’t be grown aeroponically, or not in quantities that would make economic sense, so I don’t expect vertical farming to make traditional agriculture obsolete.
But for now, we’ll have to wait and see if Aerofarms can deliver on the early promise.