There are numerous factors and elements that go into growing potent cannabis. Most salient cultivation methods focus on healthy nutrients and colossal doses of light (natural or artificial).
However, there are some aggressive, lesser known tactics that intentionally stress the plant in order to boost cannabinoid levels or produce higher yields.
Positive Stress in Plants and Humans
All living creatures experience some form of stress, which is critical to survival. In humans, psychologists have linked healthy doses to an increase in motivation and cognitive abilities. But, as with many things in life, balance is key to reaping the benefits of strain. For example, prolonged emotional pressure could make you feel depressed and more prone to illnesses (but will make you more resilient as you overcome such challenges).
Like humans, plants need stress to evolve to changes in their environment. For instance, natural wildfire is often viewed as catastrophic around highly populated areas. In the wild, this phenomenon is vital to the growth of numerous plants. According to Dr. Timothy B. Mihuc, Professor of Environmental Science in SUNY Plattsburgh, some plants have evolved to generate seeds after forest fires. So without exposure to such stressful events, they would not be able regenerate in abundance.
When exposed to water-related stress, scientists have observed the production of thick leaf cell walls – making them more resilient. Abiotic stress in plants – both positive and negative – is difficult to observe, because they can’t vocally express their status. Furthermore, the effects of strain are typically not instant in the living organisms. Stunted growth, brittle leaves or discoloring do not arise after weeks into the growing cycle.
“While no formal studies have been completed, heat and drought stress [in cannabis plants] can increase resin production as long as the stress is not excessive in nature,”
said Jason Nelson, Master Grower for Cresco Labs in Illinois.
High Stress Training (HST)
One of the most common set of stressing methods applied to cannabis plants in their growing cycle is called high stress training (HST). There are several techniques in this category; all with the main goal of subjecting the plant to certain amounts of stress, while allowing it to bounce back and recover.
Topping refers to physically dismembering the top portion of the plant with your hands. If done correctly, the buds at the top should turn into branches. This practice also causes it to grow branches in the lower sections. In the wild, this is comparable to an animal biting off a part of the plant, sending it into survival mode. A more invasive version of topping involves cutting certain parts and amounts of the top, causing it to produce four branches. Improper execution could leave the cannabis plant more prone to infection.
Super cropping is another HST technique that inflicts physical stress on cannabis. The method requires the grower to bend or pinch the stem until the internal component breaks. The outer part of the stem should not be damaged. If done properly, the plant will simply flop over, unable to support itself. To the untrained eye, the plant will look severely damaged and unusable.
Cannabis that has been super cropped “thinks” its main stem has been lost. As a result, it goes into growing mode, in an attempt to “re-grow” the “missing” stem and its lower branches. Sadly, the part that has been super cropped will never grow in a vertical position and will stay in its horizontal position. However, new branches should appear around the damaged areas. An obvious risk to this technique is damaging the outer stem and failing to provide the right environment for the herb to fully recover.
Light Deprivation and UV-B
Some outdoor growers in warm-temperate zones deprive their cannabis crops of sunlight to forcefully enter the flowering stage. To accomplish this, cultivators cover the plants with light-proof material for roughly 12 hours per day. Monitoring is a must when implementing this method, as the herb is prone to overheating, mold growth (from increased moisture), as well as a decrease in plant size and yield.
Another technique that involves light includes exposing cannabis to ultraviolet light in the B spectrum (280–315 nm). This type of ultraviolet radiation is damaging to humans; it is primarily responsible for causing sunburn and skin cancer. Cannabis plants “feel” a need to defend themselves from UV-B rays, by producing more THC and resin. It is unclear how THC protects the herb from harmful UV-B light.
“The use of UV-B light will help increase THC and resin production up to a point. The plant will need to veg under increased UV-B so that it is used to it in the flower phase,”
explained Danny Sloat, Founder and Master Grower at AlpinStash.
To Stress or Not to Stress?
There’s no doubt that stress can make cannabis plants more resilient and potent. However, the quality of the buds may also be affected during the process. Due to the risks involved, such practices for commercial growers are considered to be non-essential.
Without being able to accurately gauge a plant’s reaction to strain and pressure, cultivators may focus more on providing a conducive growing environment and robust nutrients. From a business perspective, reducing stress in cannabis helps improve consistency during harvests, allowing retailers to offer flowers with uniform cannabinoid profiles. In order to compete with pharmaceutical medication, dispensaries must be able to regulate the quality of their products, which undeniably starts at cultivation.
“The adage holds, a bit of stress is a good thing, but a bit too much stress pushes well into the point of diminishing returns. Insight on possible benefits to cannabis under a controlled stress environment is an underdeveloped principle,” highlighted Nelson.
To conclude, knowing that some cannabis plants go through stress in their life cycle may help instill a great sense of appreciation for the herb. The practice of intentionally stressing cannabis plants is comparable to adding spices while cooking. Miniscule, regulated amounts are more than welcome and can improve the flavor of the dish. Too much could wreak havoc on the meal, making it unsuitable for consumption.
This post was originally published on May 24, 2017, it was updated on October 5, 2017.