When it comes to optimizing yield per square meter, minimizing crop stress, and achieving consistent quality in leafy greens production, there are multiple opinions on how to do so. Different experts often recommend different strategies, settings, and fine-tuning approaches.
However, after years of experience in fresh vegetable production, we have consistently observed a common issue: the fundamental plant processes are often misunderstood. This frequently leads to incorrect decisions, inefficient practices, and ultimately suboptimal results.
To address this gap, we have outlined the three essential, manageable plant processes that every grower must understand and control in order to achieve high-quality production in Controlled Environment Agriculture (CEA) systems.
Photosynthesis: The Driver of Growth and Yield
Photosynthesis is the primary process responsible for biomass accumulation. In other words, the only process that directly increases plant dry matter (and ultimately fresh weight).
This process is influenced by three key factors:
- PAR light (Photosynthetically Active Radiation) reaching the canopy
- 24-hour temperature regime (day and night)
- CO₂ concentration during daylight hours
These factors work in combination to determine the rate at which plants produce sugars. These sugars are then used to build dry matter, which directly translates into crop weight and yield per m².
By carefully optimizing light intensity, temperature strategy, and CO₂ levels, growers can significantly increase photosynthesis efficiency, resulting in faster growth and higher productivity.
Respiration: Used for plant maintenance
Respiration is often overlooked, yet it plays a critical role in plant performance. Unlike photosynthesis, which builds biomass, respiration consumes sugars to maintain plant functions, especially under stress conditions.
Key points to understand:
- Respiration occurs 24/7, both day and night
- It increases under stress conditions such as high temperature or excessive light
- High respiration reduces the amount of energy available for growth
Modern cultivation strategies, such as RTR (Radiation Temperature Ratio) models, help define optimal boundaries for light and temperature to avoid excessive respiration.
A critical takeaway for growers:
More energy input does not always mean higher yield.
In many cases, excessive light or heat can increase respiration to the point where growth efficiency actually declines.
This is why balancing light and temperature is one of the most important factors in CEA production.
Transpiration: Plant breathing
Transpiration is the process by which plants move water through their system and release it into the environment. It is essential for both plant health and product quality.
This process contributes to:
- Cooling the plant, reducing stress and respiration
- Maintaining stomata function, preventing physiological disorders
- Transporting water and nutrients to growing tissues
Transpiration is primarily influenced by:
- Stomatal activity
- Humidity deficit (H.D)
When the surrounding air allows for proper transpiration (balanced H.D), plants can efficiently transport nutrients, particularly calcium. Poor transpiration is a common cause of issues such as:
- Tip-burn in leafy greens
- Uneven coloration
- Nutrient deficiencies
In many cases, what appears to be a nutrient issue is actually a transpiration imbalance.
Bringing It All Together
While each of these processes: photosynthesis, respiration, and transpiration play a distinct role, their interaction determines overall crop performance.
Growers and operational managers need to understand how to:
- Maximize photosynthesis
- Minimize unnecessary respiration
- Maintain balanced transpiration
This integrated approach is essential for achieving high yields, consistent quality, and efficient resource use in modern CEA systems.
Continuous Learning and Practical Application
A full understanding of these processes cannot be achieved through theory alone. It requires practical experience, data interpretation, and precise environmental control.
At Agranom, we support growers, companies, and investors through tailored training and workshop programs, combining in-depth theory with real-world application in commercial leafy greens facilities.
If you are interested in developing your knowledge and improving your production performance, visit our website to learn more: https://agranom.nl/services/
