Cannabis potency refers to the concentration of psychoactive compounds, specifically tetrahydrocannabinol (THC). Consumers often assume a darker hue indicates superior strength, but this idea is misleading. The chemical composition that dictates potency is entirely separate from the pigments that give the plant its color. Accurately assessing quality requires understanding the difference between visual cues and chemical metrics.
Debunking the Myth: Color vs. Chemical Potency
Brown cannabis is not an indicator of increased strength; it is usually a sign of age, improper storage, or poor quality, resulting in reduced potency. Fresh cannabis is vibrant green due to high amounts of chlorophyll. As the cannabis ages or is exposed to harsh environmental factors, the chlorophyll breaks down, causing the color to fade to duller shades of yellow, tan, or brown.
Discoloration happens concurrently with the chemical degradation of cannabinoids, especially THC. Exposure to heat, light, air, and humidity causes THC to break down into other cannabinoids, such as cannabinol (CBN). CBN has a much milder or more sedating effect compared to THC, meaning the overall psychoactive strength of the product is significantly diminished.
The color of cannabis is determined by various pigments, including chlorophyll, carotenoids, and anthocyanins, none of which directly correlate with THC concentration. For instance, purple hues are caused by anthocyanins, influenced primarily by genetics and cooler growing temperatures, not the amount of THC present. A vibrant color may signal a desirable terpene profile or a healthy plant, but it does not equate to higher potency.
Causes of Cannabis Discoloration
Improper drying and curing is a common reason cannabis develops a brown or muted color. Curing slowly removes moisture and breaks down residual chlorophyll, resulting in a smoother smoke and a vibrant green color. If the flower is dried too quickly or exposed to excessive heat, the chlorophyll is not broken down correctly, leaving the buds with a dull, yellowish-brown appearance. This rapid process can also negatively impact the integrity of the delicate trichomes, where cannabinoids and terpenes are stored.
Oxidation and age are significant factors contributing to discoloration and potency loss. Oxidation occurs when oxygen reacts with THC molecules, accelerating the breakdown into CBN. Prolonged exposure to air and light, especially ultraviolet (UV) light, speeds up this degradation, causing the flower to lose its fresh color and become brittle. Even under optimal storage conditions, cannabis loses an average of 16 percent of its THC content after just one year.
Dark brown or black spots, rather than a uniform brown hue, can indicate a serious quality failure related to moisture and fungal growth. When cannabis is stored in an environment that is too humid or not properly ventilated, it becomes highly susceptible to mold and mildew. This type of discoloration is a major health risk and a definitive sign that the product is unsafe for consumption.
The True Indicators of Cannabis Strength
The only reliable measure of a product’s strength is its certified cannabinoid concentration, determined through laboratory testing. THC (tetrahydrocannabinol) is the compound primarily responsible for the psychoactive effects, and its content is typically displayed on product labels as a percentage. For dried flower, THC percentages above 20% are considered high potency, while products below 10% are considered mild.
Beyond the raw concentration of THC, the overall experience is significantly shaped by the product’s terpene profile. Terpenes are aromatic compounds that give cannabis its distinct smell and flavor. They are believed to work synergistically with cannabinoids in a phenomenon known as the “entourage effect.” While terpenes do not directly determine potency, they modulate the intensity and type of effect felt.
The potential strength of the final product is also largely predetermined by the plant’s genetics and the quality of its cultivation. Different strains are bred to produce specific ratios and amounts of cannabinoids like THC and cannabidiol (CBD). Factors like the quality of lighting, nutrient supply, and the timing of harvest all play a role in maximizing the plant’s genetic potential for producing potent compounds.