Analytical Variance: The Farm
In our Shelf Testing series, we re-test strains from local dispensaries. Variance is the recurring theme, because of the inherent variability in the plant and the final product. As we’ve discussed, there are several contributing factors. In the first of this two-part series, Patrick Ray – one of our Pree field reps and former grower – helps us understand some of the implications on the farm side.
Essentially every practice in a farm’s operations can affect the chemical composition of the plant and therefore its potency, terpene profile and overall quality, including the growing environment, watering styles and plant maintenance. Let’s go through each.
The growing environment plays a critical role in determining the chemical composition of the cannabis plant, which can significantly impact the variance in testing results.
- Temperature — Even small variations in temperature can affect certain strains. Producers face the common challenge of keeping rooms cool enough. Did you know that A/C exposed to plants clog easily and frequently with THC and plant matter? And plants exposed to high levels of heat for too long adversely affect overall growth and THC levels. Even a few days of variable temps can change how well the plants will develop and produce.
- Air Flow — Indoor producers avoid stagnant warm air pockets. While fans help circulate air flow, positioning is important. Air blowing directly on plants can affect their growth.
- CO2 Levels – We all know plants need carbon dioxide. Similar to maintaining the perfect temperature, having too much or too little CO2 can lead to growth issues, including a plant’s ability to produce buds. While CO2 systems use natural gas to pump into grow rooms, producers must constantly monitor levels. Short amounts of time in less-than-optimal levels (too much CO2) can kill plants quickly.
- Lighting — Producers want light reaching all areas of the plant, but light too close to the tops can decrease THC levels in the “A” buds. And too little light can lower THC levels. Strains need different levels, and changing light exposure can require altering other factors like nutrients and watering.
Every strain is different, which means there is no one-size-fits-all approach to watering. A plant under lights in a warm environment needs water consistently. Also, the frequency of watering often changes throughout the growth process.
- Overwatering can result in root rot. When roots are wet consistently, the plant begins to die. Overwatering forces the plant to be in survival mode. It’s dedicating nutrients to rebuilding its roots and staying alive, rather than bud growth and development. These plants often become stunted. The buds they produce are not fully developed and therefore lower in potency.
- Underwatering can shock the plant, which also forces it into survival mode. Similarly, the plant dedicates all of its resources to its roots, rather than bud growth. If a plant has no water for 24 hours, it can die within 24 hours. Once a plant goes too long without water, it is difficult to make it healthy again. These plants will either die or produce very little and lower potency buds.
Plant maintenance is essential for keeping plants healthy and thriving throughout their growth cycle. Growers must know their plants well and meet their different needs.
- Smaller plants dedicate less nutrients to branch and root growth, in favor of bud growth. They allow for more top bud or “A” buds (over “B” buds), which give you higher THC potential across an entire batch.
- Larger plants require more water, nutrients and maintenance, including transplanting, removing under-trim, and defoliation. How much you under-trim will determine the volume of “A” versus “B” buds.
- Adequate space for growing is also essential for healthy bud development. Producers must consistently spread out the branches so light can reach all areas of the plant. This is more necessary for larger plants; some indoor growers with smaller plants may not need the extra step. If producers wait too long to re-space, they risk stunting growth and creating more “B” buds if light can’t reach the entire plant.
Because the OLCC does not directly regulate the specific environmental conditions of cannabis cultivation, producers are responsible for developing their own best practices to determine optimal growing conditions. In the absence of standardization in cultivation practices, the industry will always breed variability.
Stay tuned for our next installment of Analytical Variance: The Lab
(Photo Source: https://www.greenhousegrower.com/)