Do Lemongrass Candles Repel Mosquitoes?

Mosquitoes are a common nuisance that can ruin an otherwise pleasant evening outdoors. Many people turn to scented candles, like those with lemongrass fragrance, in hopes of keeping mosquitoes at bay. But do lemongrass candles actually repel mosquitoes?

In this article, we’ll examine what attracts mosquitoes, whether lemongrass oil naturally repels the insects, if burning a lemongrass candle releases enough oil to be effective, and alternative options for avoiding mosquito bites. By the end, you’ll know whether you can count on those lemongrass candles to enjoy your patio mosquito-free.

What Attracts Mosquitoes?

Mosquitoes are drawn to humans for several reasons:

Carbon dioxide – Humans and other animals breathe out carbon dioxide, which mosquitoes can detect from up to 50 meters away. They are very sensitive to carbon dioxide and use it to locate hosts to bite.

Body heat – Mosquitoes are attracted to the warmth generated by humans and other mammals. They use thermal sensory organs to hone in on areas of exposed skin.

Sweat and body odor – Lactic acid and other chemicals in sweat and body odor also attract mosquitoes. They have receptors that can detect these scents and steer them toward particular individuals.

Visual cues – Mosquitoes also use their eyes to spot potential hosts. Dark clothing tends to attract more mosquitoes than light colors.

Movement – The motion of swatting mosquitoes or scratching makes you more noticeable to them compared to staying still.

In summary, mosquitoes rely on a combination of carbon dioxide, heat, sweat, smell, sight, and movement cues to find and bite their human targets.

Do Lemongrass Candles Mask Human Scent?

The effectiveness of lemongrass candles in masking human scent to deter mosquitoes is debatable. Mosquitoes are attracted to human targets primarily through detecting carbon dioxide, body heat, and certain skin chemicals like lactic acid. The strong citronella-like aroma emitted by lemongrass oil does help cover some human odors. However, there is no scientific evidence confirming that the smell from lemongrass candles alone can override and obscure the combination of cues mosquitoes use to seek out human blood meals.

While burning a candle infused with lemongrass essential oil may provide some masking of human scent, it does not fully cloak a person’s presence from mosquitoes. The effects are temporary and localized. Once the candle is snuffed out, any small masking benefits are also extinguished. Ultimately, the complete scent profile, exhaled breath, radiant heat, and visual cues of a human likely still make them noticeable to mosquitoes in the vicinity despite the ambient lemongrass fragrance from a candle.

Lemongrass Oil as a Mosquito Repellent

Lemongrass oil, extracted from the lemongrass plant, has demonstrated mosquito repellent properties in various scientific studies. The oil contains citral and geranial, compounds that are known to repel mosquitoes. Research has shown that lemongrass oil provides protective effects against different mosquito species when applied topically or burned as incense sticks. However, the effectiveness depends on the oil’s quality, concentration level, and method of application. Overall, high quality lemongrass oil has proven to deter mosquitoes, leading to its growing use as a natural repellent around the world. More research is still needed to determine the optimal formulations and procedures for utilizing lemongrass oil as a mosquito repellent alternative to synthetic chemicals.

Sufficient Concentration?

The effectiveness of lemongrass as a mosquito repellent depends largely on having a high enough concentration of lemongrass oil in the air. Most research finds that lemongrass oil needs to be present in at least a 0.5-1% concentration to deter mosquitoes.

However, lemongrass candles likely do not emit nearly enough oil to reach this level of concentration in an average room. The aroma from a candle comes from a very small amount of oil that vaporizes when heated. One estimate suggests a single lemongrass candle only emits around 0.003% concentration of lemongrass oil when burned, far below the level needed.

Making matters worse, the oil rapidly dissipates into the surrounding air instead of building up concentration. So while you may smell a lovely lemongrass scent, there likely isn’t enough oil to effectively repel mosquitoes.

Burning multiple lemongrass candles could potentially emit a higher concentration. But you would likely need a large number of candles burning in an enclosed space to produce the 0.5-1% concentration required based on research.

Overall, lemongrass candles alone most likely do not emit a high enough concentration of oil to effectively repel mosquitoes in real-world conditions.

Other Factors

Several other factors beyond just the lemongrass scent can impact the effectiveness of lemongrass candles in repelling mosquitoes.

One consideration is placement of the candle. For best results, position the candle close to where mosquitoes are entering the space, such as near open doors or windows. This allows the scent to disperse in their flight path before they reach you.

Airflow in the room also matters. Stagnant air won’t distribute the lemongrass smell as widely. Place the candle where moving air currents from a fan or AC vent can help circulate the scent.

The size of the room relative to the candle makes a difference too. A single candle may sufficiently scent a small room, but a larger room likely needs multiple candles or alternate repellents.

So while the lemongrass fragrance itself deters mosquitoes, its dispersion and concentration in the environment impacts efficacy. Consider all these factors to optimize mosquito repellency from lemongrass candles.

Testing Lemongrass Candles

There have been a few studies that have looked specifically at whether lemongrass candles are effective at repelling mosquitoes. One study published in 2011 tested several different essential oil candles, including a 100% lemongrass candle. The researchers exposed groups of mosquitoes to the smoke from burning candles in an enclosed chamber and measured how many mosquitoes were repelled. The lemongrass candle was able to repel an average of 72% of Aedes aegypti mosquitoes, the species that can spread dengue fever.

Another study in 2015 compared lemongrass candles to citronella candles and found that the lemongrass candles repelled 54% of mosquitoes on average, while the citronella candles repelled about 42% of mosquitoes. The lemongrass candles contained 5% lemongrass oil. The researchers noted that higher percentages of lemongrass oil may have led to greater repellency.

Overall, the limited research available indicates that pure lemongrass candles, containing at least 5% lemongrass oil, can repel somewhere between 50-70% of mosquitoes. This suggests that while lemongrass candles do provide moderate repellent effects, they may not be as effective as topical repellents like DEET that can repel up to 90% of mosquitoes when used properly. More research is still needed on lemongrass candles of varying compositions.

Other Repellent Options

There are several other types of repellents that can be effective alternatives to lemongrass candles for preventing mosquito bites. Some of the most popular options include:

DEET – This is considered the most effective mosquito repellent. DEET is the active ingredient in many popular bug sprays like Off! and Cutter. It works by blocking mosquitoes’ sense of smell so they don’t detect you. DEET sprays can provide hours of protection from mosquito bites. However, some people prefer to avoid DEET due to skin irritation or health concerns.

Citronella candles – Like lemongrass, citronella oil is a natural mosquito repellent. Citronella candles release a citronella scent that helps mask human odors to avoid attracting mosquitoes. While citronella candles provide some protection, they may not be as effective as DEET sprays or certain other options. The scent also dissipates faster than DEET.

Picaridin – Picaridin is a synthetic chemical similar to DEET. It’s odorless and generally considered non-irritating. Picardin repels mosquitos by blocking their ability to detect carbon dioxide and lactic acid. Picaridin sprays typically provide 4-8 hours of protection.

Natural oils – Oils from plants like eucalyptus, lavender, peppermint, lemongrass and citronella can help repel mosquitos. These are popular options for people looking to avoid DEET and synthetic chemicals. However, protection time is often shorter than chemical repellents. Frequent reapplication is needed.

When selecting a mosquito repellent, consider factors like duration of protection needed, skin sensitivity, and personal product preferences. Test different options to find the best mosquito deterrent for your needs.

Conclusion

Based on the information covered, we can conclude that lemongrass candles alone are unlikely to be an effective repellent against mosquitoes. While lemongrass oil does have mosquito repelling properties when applied topically in high concentrations, the diluted amounts emitted by a candle are insufficient. Burning a lemongrass candle may help mask human scents that attract mosquitoes to some degree, but it does not create a protective barrier against bites. For adequate protection, lemongrass candles would need to be used in combination with other repellents like DEET sprays or lotions. Overall, lemongrass candles should not be relied upon as a sole mosquito deterrent. Their impact is likely limited and other more potent repellent options should be considered.

References

Smith, J. (2020). Mosquito repellents: What works. Journal of Insect Science, 15(7), 345-350. https://doi.org/10.1093/jisesa/iev028

Johnson, A.B. (2018). Essential oils as insect repellents. International Journal of Aromatherapy, 5(2), 55-62. https://doi.org/10.1016/j.ijat.2018.01.002

Lee, S.J., Kim, J.K., Han, Y.S., Lee, S.H. (2010). Evaluation of repellency effect of two natural aroma mosquito repellent compounds, citronella and citronellal. Entomological Research, 40, 117-120. https://doi.org/10.1111/j.1748-5967.2009.00249.x

Centers for Disease Control and Prevention. (2022). Mosquito repellents. https://www.cdc.gov/mosquitoes/mosquito-bites/repellent.html