Crop steering has captured the cannabis industry. By manipulating plants between vegetative and generative development, growers are getting much greater returns at harvest time.
However, nailing crop steering at the commercial level requires complete control over the grow room environment, including lighting, irrigation, and climate. Each of these levers works to increase or decrease stress conditions, all while playing off one another.
Here, we get into the fundamentals of one of these levers: climate. Discover how temperature, vapor pressure deficit, and humidity are applied to drive vegetative and generative growth.
Crop steering is a cultivation technique that evolved in conventional indoor agriculture but is now being used for cannabis cultivation. It involves carefully manipulating the growing environment to guide a cannabis plant's development towards desired outcomes, flipping the plants between higher and lower states of stress.
Higher environmental stress leads to generative growth, while lower stress encourages vegetative growth. Crop steering utilizes climate, irrigation, and lighting to steer the plant towards either vegetative growth (leaf and stem development) or generative growth (flower/bud development). When done correctly, growers optimize plant development for more flowers, greater flower size, and, overall, greater yields.
There are three avenues growers use to pull plants between vegetative and generative growth: lighting, irrigation, and climate. Each lever plays a role in increasing or decreasing a plant's stress level, although each is interconnected.
Temperature, humidity, and vapor pressure deficit (VPD) are the three most important climatic cues. Subtle adjustments to one climate parameter will quickly impact others. As cultivators experiment with dry backs and lighting intensity, they'll also integrate subtle changes to the indoor climate to further push the plants in the targeted direction.
Of course, the grow room still must stay within reasonable parameters to keep pest and disease risk at a minimum while maintaining a suitable environment for plant growth. Yet, even within this safe zone, there is a substantial amount of room to play with to optimize yields.
A lower VPD is ideal during the vegetative stage. This reduces the rate of water loss through transpiration, allowing plants to retain more moisture, which supports the development of leaves and stems.
To enhance busy, leafy vegetative growth, the grow room requires slightly higher temperatures and lower humidity than those used in the flowering phase. At this stage, growers can also reduce ventilation circulation to some degree.
Finally, because vegetative growth requires a generally lower-stress environment, it's also important to consider day-to-night shifts and their duration. It's recommended to keep temperature swings between day and night less drastic than what you'd see in flower, and to make the changes between the two periods much more gradual.
Generative (or reproductive) growth is better supported by a higher VPD, higher humidity, and lower temperature. Setting the VPD range between five to seven grams per cubic meter (1.0-1.5kPa) encourages more vigorous transpiration rates, steering plants towards flowering and reproductive activities.
This environment, characterized by higher moisture levels (greater humidity), prompts an increased uptake of water and nutrients, crucial for optimal flower production.
Keep in mind that with higher humidity, the room's ventilation needs will increase. Additional cues include transitioning from day to night more drastically and rapidly.
Altogether, these climate cues apply higher stress environmental conditions to push the plant's hormonal response into reproductive-driven growth patterns.
Realistically, the only way to crop steer with climate is to have unprecedented control over the grow room, a level not feasible without automation and data. Without pulling real-time data from across the grow room, the ability to analyze that data, and then the means to adjust for it, you will not be able to drive the desired outcomes.
Furthermore, should the grow room move outside your predetermined parameters, you'll need a centralized monitoring system available to respond.
The GROWHub Environmental Monitoring platform is an autopilot solution for growers who need real-time data to actively monitor, control, and analyze past and present grow cycles.
Uniquely designed to integrate data pulled from wireless sensors throughout the grow room, the software can detect even slight fluctuations in temperature, humidity, CO2, light intensity and other critical parameters. This allows for immediate responses to environmental changes, safeguarding plant health by preempting potential issues.
GROWHub is perfectly synchronized with TSRgrow's Advanced LED Lighting systems and remote power servers, creating customized lighting zones, for strain specific recipes. With control centralized into a single, easy-to-navigate dashboard, growers can optimize the room, whether it's a single or multi-stain space.
This revolutionary system contains advanced data and reporting capabilities, giving growers the insights needed to review past harvests and adjust processes for better future outcomes. This level of detailed analysis aids in achieving optimal yields and improving overall facility outcomes.
Upgrade your crop steering strategy with a grow room solution to help you manage, track, and autonomously control your environment.