For the team at the Philips GrowWise Research Center in Eindhoven, Netherlands, days are filled with exploring the potential of controlled indoor environments to optimize growing conditions, crop quality and yield. Signify Plant Specialist Jarno Mooren is one of the researchers located at the Center. His work focuses on designing and running trials aimed at developing growth recipes to help growers grow crops more efficiently and profitably. That research encompasses light, cropping systems, climate and nutrients for a wide range of common CEA (controlled environment agriculture) crops. He recently shared the latest results from some intriguing tomato trials carried out at the GrowWise Research Center.
As Mooren explains, thoughts of greenhouse tomatoes typically evoke images of rows upon rows of indeterminate plants skyrocketing upward. While these towering varieties can help extend the season and produce high yields, they come with a unique set of challenges due to the tall, indeterminate growth habit. Among those challenges, Mooren says, is the requirement for a single-layer, high-wire growing system, paired with wide row aisles to facilitate maintenance and harvest. For growers with limited space and/or labor — often common for indoor urban agriculture — those basic requirements put a significant crimp in tomato possibilities.
In recent years, GrowWise Research Center trials on various indeterminate tomato plants have helped develop strategies and practices to maximize crop productivity and quality. However, the associated challenges begged the question: What if there were a better way to grow tomatoes?
“Not only did we simplify the growing cycle and reduce labor costs, but we also found that we could harvest nearly 1.5 to 2 times more tomatoes per square meter per year compared to traditional greenhouse farming.”
Circumventing indeterminate tomato challenges
“To make indoor tomato farming more profitable, we had to overcome two major obstacles: (1) finding ways to make the most of the limited space, while (2) reducing labor costs,” Mooren shares. “And we were not the only ones to acknowledge and address these challenges. Certhon has partnered with HW Seeds and developed a new system called Gronos. They use varieties of bush tomatoes, which don’t need as much maintenance and produce ripe fruit all at once. Walkways can be removed to make room for plants, as workers don’t have to move around for crop maintenance and harvesting. They have found this works well for outdoor production of tomatoes, but how does it work for indoor farming?”
As a result, the GrowWise team decided to trial smaller bush tomato varieties in high-density, multi-layer indoor systems, harvesting them all at once at the end of their cycle. “We conducted several trials to test this strategy and see if it could produce as much fruit as traditional high-wire systems, with less labor. The results are promising,” Mooren says. “Not only did we simplify the growing cycle and reduce labor costs, but we also found that we could harvest nearly 1.5 to 2 times more tomatoes per square meter per year compared to traditional greenhouse farming. This means we can produce more tomatoes with less effort and fewer resources, making it a promising strategy for more sustainable and profitable indoor farming.”
Refocusing on quality and ripening homogeneity
He adds that, while the market demands both high quality and exceptional flavor in cherry tomatoes, achieving those qualities and optimizing the potential for automated harvesting hasn’t been simple. “To improve overall quality, our current research focuses on managing key parameters such as fruit structure, taste and shelf-life,” he says. “Additionally, we aim to improve the ripening homogeneity of cherry tomatoes so that all fruits ripen at the same rate, making automation simpler with a single mechanic harvest.”
Mooren shares that, while many cherry tomato varieties currently available were originally developed for the decorative market rather than high quality or yield, a shift is underway. “The good news is that more companies in the industry are now investing in this new way of growing tasty cherry tomatoes. With continued research and development, we hope to meet the demand for high-quality and delicious cherry tomatoes in the marketplace,” Mooren says.
The work at the GrowWise Center suggests that growing determinate tomatoes in high-density, multi-layer systems holds great promise for CEA growers focused on maximizing production with reduced labor costs. For Mooren and the GrowWise team, their work will continue to focus on the improved fruit quality and ripening homogeneity of cherry tomatoes they see as essential to meet consumer demand. We look forward to future updates on how the team’s techniques and results evolve.
Image: Jarno Mooren, courtesy Signify