A Prescription from the Gro Doctors
by John Vivichhia
These days master growers are often pressured by management to squeeze more and more yield out of their grow facilities to drive operational profitability, The Bottom Line. It makes sense, right? Profits are king!
But pushing yields stresses more than just the master grower and plant technicians. It also pushes the limits of grow and environmental systems, and more often than not results in exactly the opposite effect.
When vapor pressure deficit (VPD) cannot be controlled within the total volume of the grow space, plants suffer from stresses that typically result in lower yields, diminished cannabinoid and terpene production, and crops that are more susceptible to failures due to mildew, pests, and other pathogens.
Pathogen and mold problems can quickly become uncontrollable when relative humidity (RH) levels rise too high and temperatures (T) drop too low, a common occurrence in improperly designed Heating, Ventilation, Air Conditioning, and Dehumidification (HVAC/D) systems. And this often happens late in flowering cycles when canopy and flower densities are at their highest. This ultimately leads to late stage total crop failures at worst, and failing stringent mandatory testing standards at best.
Alignment of a HVAC/D system’s capacity to maintain optimum levels of T, RH, and VPD with the grow space’s sensible heat loads, and room and plant evapotranspiration levels, is paramount to optimizing a grow facilities ability to produce consistent, reliable harvests at peak production levels. The first step is determining what load capacities the environmental system is truly capable of controlling, and understanding what’s happening environmentally within a grow space in three dimensions and at sensing densities high enough to allow visualization of any microclimates within the grow space.
Many grow operations rely on single or dual point environmental sensors (T/RH) to monitor and control their HVAC/D equipment in large volume grow spaces. But a grow room is a complicated environment. Inconsistent airflow supply and circulation, combined with HVAC/D equipment that cannot meet grow space environmental loads, often promote microclimates within the plant canopy and grow space creating a large range of less than optimal VPD conditions where healthy plant growth cannot be achieved and where pathogens, such as powdery mildew (PM), can thrive and quickly spread.
Visualizing the grow room environment in three dimensions, throughout the canopy, is instrumental to identifying and rectifying an inhomogeneous VPD environment. And further, aligning a HVAC/D system’s capacity to hold optimal VPD conditions over the entire volume of a grow space is the first step to maximizing yields, and creating quality, consistent harvests that enhance the Bottom Line.
The iQ Family of Solutions from Orion Partners.ai – Gro iQ and Capacity iQ – can help your Operational Team deliver a comprehensive system plan to ensure success in YOUR facility.
John Vivichhia is a member of the technical staff at the Massachusetts Institute of Technology – Lincoln Laboratory and has 30 years experience growing cannabis.