Does vertical farming offer a growth solution to Scottish agriculture?

The Scottish Farmer visited the James Hutton Institute, in Perthshire, which has been home for the last 18 months to Scotland’s first vertical farm, designed and built by Intelligent Growth Solutions (IGS), led by CEO, David Farquhar.

The vertical farm measures 25m by 12m and stands 10m high. It contains four growing towers, each containing up to 60 stacked trays each measuring 6.25 square metres (about the size of a snooker table). During a tour of the facility, Mr Farquhar explained why this innovative growing system could be a solution for Scottish farmers.

“What we are doing here is researching, testing and fine-tuning to create the perfect conditions for plant growth in a controlled environment. This means we can closely monitor variables such as irrigation, disease, sunlight and ventilation, to generate the optimal conditions for growth.”

The farm uses rainwater to irrigate the plants. The water system is on a closed loop which minimises loss by recovering run-off water and harvesting the humidity created through transpiration. This is then condensed and all recovered water UV-filtered before returning to the system. Each time watering takes place, selected nutrients are added to promote plant growth.

“In a greenhouse, it can take around 30 days for certain herbs to reach maturity. We are achieving this in 20 and that allows us to operate 50% more growth cycles per annum,” he explained. “We are also finding that for a given area, instead of harvesting say 450 grams of cut produce, we are yielding 680-700 grams in two-thirds of the time.”

The ‘farm’ entrance has an air-lock to minimises the chance of introducing pests and a recent local authority microbiology test found it to be one of the cleanest growing environments it had witnessed. Strict bio-security eliminates the need for pesticide use and cameras on the plant trays allows monitoring of plant development and for disease or spoilage.

“The cameras check for things like leaf damage, disease and bugs but also crop development. The key is to compare growth and quality against your expectations for a given ‘recipe’ of weather,” he pointed out.

“These parameters can be adjusted by the farmer, or automatically, using new weather recipe suggestions generated by our software. The grower can keep tabs on progress using our smartphone app from anywhere at any time. The system is managed via the internet as our engineers have eliminated the need for a lot of computers and cables, so there is no big IT burden for the farmer to worry about.” Mr Farquhar added.

What sets Scotland’s vertical farm apart from others world-wide is that it has arguably the most advanced power management, controls, mechanics and ventilation system developed to date. For example, ‘sunlight’ is optimised using a mix of five lights, which are controlled individually for each tray allowing dimming, pulsing, colour mixes and intensity to positively impact plant growth for yield, quality and consistency.

“This allows us to have complete control over sunlight,” he explained. “They also have control over temperature and through a ventilation system we are able to create unique micro climates for each crop.

“If we equate this to an outdoor farm, it would be like taking a 10-acre field and cutting it into snooker table-sized trays with each individual tray having different weather patterns applied. This allows the farmer to operate a virtuous cycle, by ‘creating’ the weather, monitoring how it affect the crops and then altering the recipe for continuous improvement,” said Mr Farquhar.

Many people have been critical of the energy used to power vertical farming and the impact this might have on the environment, but he had an opposing argument: “At this time of year, if you look at fruit and veg in the supermarkets, many are all imported from places like Morocco or Peru – just think of the air miles and the carbon footprint that delivers.”

“By building a vertical farm you can grow as close to the point of consumption in a city or close to a distribution hub, which is why big supermarkets are looking to invest in this technology. It also reduces the amount of land which would previously be required for planting and therefore minimises its footprint, the use of pesticides and the huge costs of buying land. The great outdoors is best for growing our staple crops.”

On site at the vertical farm was crop scientist, Matthew Reid, who explained how he has been monitoring and testing different variables in a selection of basil plants, to determine the best recipe for optimal plant growth.

“Part of my role is to work with growers to identify plant quality traits of interest, for example yield, flavour, aroma and appearance. We are trying to look at how manipulating the growing environment, in particular light, can be used to control how crops grow,” he explained.

“Using a mix of different LED lights, we aim to identify light spectra which enhance particular quality traits. Farmers want to know what the fastest recipe is for yield which is what our current trials aim to identify,” he said.

“By giving us complete control over the environment this indoor growing system allows us to make plants grow the way we want them to.

“This can be by giving the plants exactly what they need to grow happily, but it can also involve providing the right amount of stress which can enhance things like flavour and pigmentation,” he continued. “For example, we have found that higher energy wavelengths of light, such as blue and ultraviolet light, can increase red pigmentation in lettuce similar to the way that these same wavelengths produce sunburn in humans,” he concluded.

Labour shortages within the agricultural sector have been well documented in recent months, with the growing pressure of accessing a future labour workforce post-Brexit making advances in automation a necessity for farming.

Mr Farquhar explained how vertical farming could work: “Currently, we are growing salads and micro greens in the vertical farm. However, soon we hope to look at growing crops such as tomatoes and soft fruit which could be a possible solution for those farmers whose businesses have been hit by poor weather and labour shortages these past couple of years.

“We advise everyone who invests in this technology that they will need to have some sort of horticultural expertise, however, what we are taking out is manual labour, as everything is controlled by robots from the likes of watering to harvesting.

“It is getting harder for farmers to access manual labour and this system removes that pressure from farmers who, once they are trained in the technology, will be able to operate the system on virtually a solo basis with support from IGS.”

Scottish farmers will soon be able to buy this technology for themselves, allowing them to set the parameters for perfect growing conditions for their crops. The initial costs of investment will. obviously, be a deterrent to farmers who have been hit hard by poor income returns over the last couple of years, however, Mr Farquhar argued that the investment would deliver huge economic returns, even in the medium term.

“Investing in this technology is a capital commitment for farmers. However, most farmers don’t buy tractors or combines but instead lease them. There is no reason why they couldn’t do something similar with our technology,” he suggested.

“We are also in talks with one of the leading agri-finance companies, AMC, who are considering offering support to farmers wanting to make this investment,” he explained.

“We’ve had Scottish outdoor growers interested in our technology to help minimise the costs of propagation. Currently, many start to grow their seedlings at the end of the season and then have to hold them at an even temperature for six months before planting out- a significant power cost given Scotland’s fluctuating temperatures.

“With IGS technology, they could grow them in a week or so using far less energy and could use the rest of the year to grow a much higher value crop, like salads,” he argued.