While plant growth mostly relies on light, water and carbon dioxide, it still needs some trace elements from soil or fertilizers to be healthy. In the case of plant factories, hydroponic nutrient solutions infused with 17 essential elements ranging from nitrogen to calcium have replaced the tilted soil.
"The content of the nutrient solution is also tailored to suit the plant's specific needs," said Pei Kequan, a research director at the factory. Unlike the trace elements from fertilizers, which are locked in big compound molecules, "the nutrients in the solution are broken into small molecules, meaning the plant can absorb them easier and grow faster while keeping its nutrient value and taste".
It takes about 20 days for a sapling to reach maturity in the lab, but 40 to 60 days in a conventional farm. This means scientists can reap more than a dozen harvests of produce each year, compared with one to two harvests from a conventional farms, depending on the weather conditions, he said.
Moreover, scientists at the facility have built the infrastructure to monitor the elements in the solution. Once an element is depleted, scientist can add the missing nutrient and reuse the solution without needing to make a new batch, thus reducing the cost.
"We go to great length to study and cater to our plant's most fundamental needs, making sure they could grow under the best conditions," Pei said. "In a way, the plants are the kings, and we are all its servants."
It's high time we find a sustainable and green way to protect our food security."
Li Shaohua, director of San'an Sino-Science's Photobiology Industry Institute
