Flies are a common nuisance. For cannabis cultivators, a frequent question is whether flies are particularly attracted to these plants. The relationship between flies and cannabis is complex, involving environmental and chemical factors that influence fly presence.
Why Flies Are Drawn to Certain Smells
Flies possess highly developed olfactory systems, allowing them to detect specific scents from a distance. These insects are generally drawn to odors signaling readily available food sources or suitable breeding grounds. Common attractants include decaying organic matter, such as rotting food scraps, compost, or animal waste, which provide both sustenance and a place for larvae to develop. Fermenting substances, like overripe fruit or spilled sugary liquids, also emit volatile compounds that flies find appealing. Additionally, flies are attracted to moisture and warmth, which can indicate ideal conditions for feeding and reproduction.
Cannabis and its Aromatic Compounds
The cannabis plant produces a diverse array of aromatic compounds, primarily terpenes and other volatile organic compounds (VOCs), which give each strain its unique scent profile. These compounds are found in the plant’s glandular trichomes, acting as part of its natural defense system against herbivores and pests. While some terpenes can attract beneficial insects that prey on plant pests, others are known to deter harmful insects. For instance, research suggests that cannabinoids themselves, like CBDA and CBGA, may deter insect feeding, with higher concentrations leading to less damage from certain insect larvae. Therefore, a healthy, living cannabis plant’s inherent chemistry is not typically a strong, direct attractant for common flies in the way decaying matter or sugary foods are.
Factors Encouraging Fly Presence Around Cannabis
While the healthy cannabis plant itself may not be a primary attractant, conditions often associated with cannabis cultivation or storage can draw flies. Decaying plant matter, such as discarded leaves, trimmings, or spilled product, can decompose and create odors that attract various fly species, including fungus gnats. Excess moisture or high humidity in growing environments, particularly in the soil, can also create ideal breeding grounds for flies like fungus gnats, whose larvae thrive in wet conditions. Some organic fertilizers or spilled nutrient solutions can ferment, releasing smells that attract flies. General organic waste in a grow space or near storage areas, combined with warmth, can further contribute to fly presence by providing ample breeding sites and food sources.
Strategies to Deter Flies
Effective fly deterrence around cannabis involves maintaining a clean and controlled environment. Regularly removing any decaying plant matter, such as dead leaves or spilled soil, is important to eliminate potential attractants and breeding sites. Controlling humidity levels and ensuring proper ventilation in cultivation areas helps to prevent overly moist conditions that favor fly reproduction. Proper disposal of all plant waste in sealed containers is also recommended, and for stored cannabis or products, using airtight containers prevents odors from escaping and attracting pests. Implementing physical barriers like sticky traps can help monitor and reduce fly populations, while biological controls or natural repellents like neem oil can offer additional protection without harsh chemicals.