A research project in the USA exploring the feasibility of vertically farmed wheat has found yields of 39 tonnes per hectare could be achieved within just 70 days when grown under optimum artificial conditions.
The crops were grown at Princeton University, New Jersey, in collaboration with the University of Florida and NASA using two crop models to simulate the growth of wheat in an indoor hydroponic system, taking into account CO2, light intensity, nutrients and temperature.
Dr Paul Gauthier, plant physiologist and head of the Princeton Vertical Farming Project, says: “We found that wheat grown on a single hectare of land in a 10-layer indoor vertical facility could produce from 700 +/- 40t/ha [measured] to a maximum of 1,940 +/- 230t/ha [estimated] of grain annually under optimised temperature, intensive artificial light, high CO2 levels, and a maximum attainable harvest index. Such yields would be 220-600 times the current world average annual wheat yield of 3.2t/ha.
“Under our conditions, the crop could yield 39 +/- 5t/ha per harvest and could grow in 70 days from seed to harvest, allowing for five harvests per year.”
Although no cost comparison was carried out, the cost:return ratio at current pricing in the US would be 45:1, he says.
“While the cost:return was calculated to be 45:1 and projected to be 6:1 by 2050, it is important to consider that a major part of agriculture across the world is subsidised. For most countries which depend on wheat imports at 90 per cent or more, growing wheat indoors could be an alternative that can help them achieve food security.
“Wheat is a major crop when we talk about food security and food availability in the world. Because of its importance globally, wheat was a great candidate for this study, especially considering staple crops are considered unfeasible indoor and unprofitable for vertical farming.”
Indoor vertical farming is taking off in the US – a few major players and a number of small businesses have been formed in the past three to five years, says Dr Gaulthier. Most of these farms concentrate on producing leafy greens and herbs but some are now looking into more rich and nutritious food.
“Vertical farming will not feed the world or replace traditional agriculture, but it is an additional source of food which can be a major player in achieving the increase of 77 per cent in food production recommended by FAO by 2050,” says Dr Gaulthier.
“Such a production system could also mitigate the impact of climate-led yield loss and mitigate prices.”