Cinnamon, a common kitchen spice, has long been associated with repelling various insects and pests. Many wonder if this spice truly deters pests. While anecdotal evidence is widespread, research reveals cinnamon’s potential as a natural pest deterrent and its mechanisms.
Which Pests Cinnamon May Deter
Cinnamon exhibits deterrent properties against a range of common household and garden pests. Ants are frequently cited as being repelled by cinnamon, with its strong scent disrupting their ability to communicate and navigate along pheromone trails. This disruption makes it challenging for them to locate food sources and return to their colonies. Mosquitoes also appear sensitive to cinnamon, particularly its essential oil, which has shown efficacy in repelling adult mosquitoes and even killing their larvae.
Spiders dislike cinnamon’s potent aroma, which irritates the sensitive hairs on their legs, discouraging them from treated areas. Beyond these, preliminary observations suggest cinnamon may deter fruit flies, bed bugs, silverfish, cockroaches, wasps, earwigs, thrips, and even slugs. Larger pests like rats, mice, raccoons, squirrels, and rabbits also reportedly avoid cinnamon-treated areas due to its strong smell.
How Cinnamon Acts as a Deterrent
The repellent qualities of cinnamon stem primarily from its active chemical compounds, particularly cinnamaldehyde and eugenol. Cinnamaldehyde, giving cinnamon its distinctive aroma, is a key insect-repelling component. This compound can interfere with the nervous systems of insects, disrupting their ability to locate food, mates, and navigate their environment. For instance, it specifically disorients ants by obscuring their pheromone trails.
Eugenol, another compound in cinnamon oil, also contributes to its insecticidal and repellent actions. These compounds can irritate pests’ senses, making treated areas unappealing or even inhospitable. In higher concentrations, cinnamon can have biocidal effects, killing insects and preventing egg-laying, though it primarily acts as a repellent. The phytotoxic effects of cinnamon also mean it can act as an herbicide and fungicide, protecting plants from certain diseases and pests.
Applying Cinnamon for Pest Control
Cinnamon can be applied in various forms to deter pests around the home and garden. Ground cinnamon can be sprinkled directly along ant trails, near entry points like windowsills and doorways, or around the base of plants. In gardens, sprinkling cinnamon powder on soil deters slugs, fungus gnats, and other pests, also helping prevent fungal diseases.
Cinnamon essential oil offers a more concentrated approach and can be used to create repellent sprays. One spray involves mixing two teaspoons of ground cinnamon with four cups of warm water, steeping overnight, straining, and then adding rubbing alcohol and mild liquid soap. Alternatively, a simpler spray can be made by diluting 10-15 drops of cinnamon essential oil in a cup of water. This spray can be applied to surfaces, clothing, or plants, though care should be taken with essential oils. Placing cinnamon sticks in areas where bugs gather, such as pantries, closets, or near windows, can also release their deterrent aroma.
Effectiveness and Safety Considerations
While cinnamon functions as a natural deterrent, manage expectations; it often serves as a repellent rather than a permanent solution. Cinnamon’s effects are typically temporary and require reapplication, especially after rain or when the scent fades. For significant infestations, cinnamon alone may not be sufficient, and professional pest control might be necessary.
When using cinnamon, especially essential oil, safety precautions are important. Cinnamon essential oil can cause skin irritation, redness, and even blistering upon direct contact, so it should be diluted before topical application or sprayed cautiously. Ingestion of large quantities of cassia cinnamon can be toxic. Cinnamon essential oil can be toxic to pets, including dogs and cats, so keep it away from them. Some individuals may also experience allergic reactions to cinnamon, manifesting as skin rashes, itching, swelling, or respiratory issues.