Does Citronella Repel Flies? What Works, What Fails, and Safer Ways to Use It
When the weather is nice, there’s nothing better than eating outside – and nothing more annoying than flies landing on your food and buzzing around your guests. If you’re like most people, citronella candles and plants are probably the first thing you think of to keep flies away.
Citronella is a plant-based, natural insect repellent that can help repel flies, but it does not kill them and it only works in certain situations and setups. Whether in plant, oil, or candle form, citronella’s strong aroma masks the smells that normally attract flies, making it harder for them to find those stinky scents they love.
Used the wrong way, citronella barely helps and fades quickly. Below, we’ll look at how citronella really works, when it helps with flies, and how to use it both outside and indoors – plus other scents and non-scent tricks that make a much bigger difference.
What Is Citronella?
Citronella is an essential oil that comes mainly from the leaves of citronella grass and, to a lesser extent, from some related plants. It’s widely used as a plant-based, natural alternative to chemical repellents and is commonly added to bug sprays, lotions, and candles.
The oil on citronella grass blades is the key ingredient that actually repels flies and other insects. That oil is naturally present on the plant and gets released into the air when the foliage is disturbed.
There are several ways to bring citronella into spaces that need some extra protection from flies and other insects – but first, it helps to understand the different types of citronella plants.
Types of Citronella Plants
There are two plants commonly sold under the “citronella” name:
Citronella grass (the true source of citronella oil)
Citronella geranium (a scented geranium with a citronella-like smell)
When people talk about citronella oil and the plant that actually works best for repelling insects, they are talking about citronella grass, not the geranium.
Citronella grass is the plant to choose if you want real, in-your-face, plant-based insect-repelling power. It makes a great accent around landscaping and can double as a decorative feature while helping keep insects away.
The plant grows in rounded clumps, with long blades that arch outward and down, giving it a full, fountain-like look. To get the most insect-repelling power out of citronella grass, you need to release more of its oil.
That’s where a simple trick comes in: crush or crunch the leaves and agitate the foliage to release more of the oil into the air. If you just plant citronella grass and never disturb it, you may not get the full benefit.
Citronella geranium, on the other hand, is a pretty purple-flowering plant that smells pleasant but is far less effective at repelling insects. It’s fine as a decorative plant, but it won’t give you the same results as true citronella grass.
Does Citronella Repel Flies?
The big question: does citronella actually work on flies? The short answer is yes – but probably not the way many people expect.
Citronella will not “eliminate” flies in the sense of killing them or making them disappear forever. Instead, it works by pushing them away from specific areas.
The citronella plant or oil does not actually kill flies; it repels them. The lemony smell of citronella is so strong and aromatic that it masks the smells flies (and other insects) are looking for. That makes it a lot harder for them to find and locate the stinky food and waste they love.
The scent of citronella isn’t necessarily something flies hate on its own. The problem for them is that the aroma is so strong it takes over their senses and makes feeding harder. No easy food = fewer flies hanging around your space.
There are some limitations you should know about:
Citronella candles only work while they’re burning and only within a fairly small radius.
Sprays and lotions that contain citronella need to be reapplied every few hours to stay effective.
Citronella works best as one part of a bigger fly-control plan, not as a stand-alone cure-all.
What Smells Are Flies Attracted To?
To understand why citronella helps, you first need to know what flies are normally following with their noses. In short: the stinkier, the better.
Flies are attracted to:
Garbage and food waste
Rotting fruits and vegetables
Damp, decomposing organic matter
Excrement and other strong, foul odors
Different types of flies have slightly different tastes, but they all follow strong scent trails to find food.
What Do Flies Eat?
Here are three common fly types you’ll see around homes and yards, and what they like to eat:
House flies – The classic, annoying flies that get into buildings and land on people and food. They eat overripe fruits and veggies, sugary substances, and decomposing waste and excrement.
Fruit flies – Tiny flies that hover around fruit bowls and trash. They feed on fermenting and overripe fruits (like bananas and pineapples), vinegar, sugary drinks, and sticky residues.
Blow/bottle flies – The metallic-looking flies often seen around carcasses and very rotten material. They feed on the worst of the worst: heavily decomposed animal matter and meat.
The bottom line: flies are drawn to all the smells most humans try to avoid. No matter what type of fly you’re dealing with, food and rot are what pull them in – and citronella helps by masking those smells so they’re harder to track down.
How to Use Citronella as a Fly Repellent Outside
If you’re dealing with outdoor flies, citronella is a natural place to start. The key is using the right form in the right spot for your situation.
Plant Citronella Grass in Fly-Prone Areas
If flies are a constant problem, planting citronella grass near fly-prone spaces is a great starting point. Good spots include:
Around patios and decks
By outdoor dining tables and seating areas
Around pools or near garden edges
In pots near doors and walkways
Before or after planting, crunch and rub the leaves to activate and release the oils. If you simply plant the grass and leave it alone, you may not get the full benefit of the scent.
Use Citronella Candles and Torches Around Seating Areas
For BBQs, gatherings, or anytime you’re eating outside, citronella candles and torches are an easy, inexpensive way to add a “scent shield” around where people sit.
Place candles or torches in a loose ring around tables and seating.
Light them 15–20 minutes before you eat so the scent can build up.
Expect them to work over a modest radius – wind and open space dilute the effect.
While they’re burning, the aroma can become overwhelming for insects and make it much harder for flies to find your food and drinks.
Try Citronella Oil on Skin (Diluted)
Citronella essential oil can also be used on skin when properly diluted.
Mix citronella essential oil with a carrier oil (like coconut oil) or a neutral lotion.
Apply to exposed skin and reapply every few hours as needed.
Never use undiluted essential oil directly on your skin, as it can cause irritation.
This won’t stop every fly, but it can help keep them from constantly landing on you, and it may reduce mosquito bites at the same time.
The Benefits of Using Citronella to Repel Flies
Citronella has become a go-to repellent for a reason. It’s widely available, easy to use, and a familiar option for many homeowners.
Natural and plant-based: Citronella does not contain synthetic insecticides or harsh chemicals.
Versatile forms: You can use it as a plant, in candles, in torches, in diffusers, and as part of lotions or sprays.
Attractive plant: Citronella grass provides lush greenery and a pleasant aroma for humans.
Targets unwanted insects: It mainly affects nuisance insects; beneficial pollinators like bumblebees and butterflies are usually left alone.
Just keep in mind that citronella is a repellent, not a full pest-control program. You’ll get the best results combining it with basic sanitation and other fly-reduction steps.
How to Use Citronella to Keep Flies Away Indoors
You can also use citronella inside to help cut down on house flies and fruit flies in problem spots like kitchens and entryways.
Use an Aromatherapy Diffuser
One of the easiest indoor options is a water-based diffuser with citronella oil. Place it in fly-prone spots such as:
Near the front or back door
Close to trash cans or compost pails
On a kitchen counter or windowsill where flies like to hover
Run the diffuser when you’re in the room or during times flies tend to be active. Avoid running strong essential oils nonstop in small, unventilated spaces.
Grow Citronella Plants Indoors
Citronella plants can be grown in pots indoors, where they offer greenery and a light, pleasant aroma.
Place pots near sunny windows or doorways.
Gently bruise a few leaves now and then to release more scent.
If you have pets, especially cats or small animals, check with your veterinarian before using strong essential oils like citronella indoors.
Where Can I Use Citronella?
Citronella can be used almost anywhere you need a bit of extra protection from flies. The best form depends on the location.
Outdoors
Around patios, decks, and porches
Near pools and sitting areas
Along garden borders or walkways
In pots near front steps or doors
Indoors
On window sills in fly-prone rooms
Near trash cans or recycling bins
In entryways where flies tend to sneak in
Candles work best in the middle of tables or on side tables. Outdoors, position torches and candles upwind of where you sit so the scent drifts across your space instead of away from it.
What Other Smells Will Keep Flies Away?
Citronella isn’t the only scent that helps repel flies. Many smells humans love are exactly what flies try to avoid. You can layer these with citronella for better results.
Basil – Flies can’t stand basil. Plant it in containers near doors and seating areas or in vegetable gardens to add both flavor and fly protection.
Lavender – A classic relaxing scent for humans, but flies usually steer clear. Grow it outdoors or use lavender oil indoors.
Peppermint – The strong, cooling smell overwhelms many insects’ senses. Peppermint-based sprays can help create a fly-unfriendly zone.
Cinnamon – Whether in stick, ground, or oil form, cinnamon smells great to us but is unpleasant to many insects.
Marigolds – Colorful flowers with a scent many insects (and even some animals like deer) dislike.
Bay leaves – Use whole or crushed bay leaves near pantry areas or food storage.
Combining these plants and scents around your home helps create multiple “smell fences” that make it harder for flies to get comfortable.
Other Ways to Keep Flies Away
Even the best scents can’t control flies if your space is full of attractants. A few simple habits often make the biggest difference:
Keep Your Garbage Tidy
Use sturdy trash bags instead of throwing waste directly into cans.
Keep lids closed and wipe up spills on and around bins.
Store outdoor trash cans in drier, low-moisture areas when possible.
Close Windows, Doors, and Vents
When you’re actively dealing with flies, limit the gaps they can use to get inside. Even a door left open for a minute can invite a whole family of flies into your home.
Use Fans
Flies don’t like strong air currents. A fan aimed at a doorway, patio table, or problem window can make it much harder for them to land and stay put.
Keep Your Garden Clean
Pick up and dispose of fallen or rotting fruits and vegetables.
Regularly clean up plant debris around fruit trees and garden beds.
Remove Standing Water
After heavy rains or irrigation, check for puddles or spots where water collects. Aerate soil and drain standing water as quickly as possible to discourage insects from gathering and breeding there.
That’s a Wrap!
If you’re dealing with flies, citronella is a smart, natural place to start before you reach for harsher options.
Citronella is a plant that looks good in your landscape and serves a purpose: helping to push flies and other unwanted insects away from the areas you actually use. Used in plant, oil, or candle form – and combined with basic clean-up and a few other scents – it’s a tried-and-true method that can move you a lot closer to a fly-free home and yard.
Martínez-de la Puente, J., Merino, S., Lobato, E., Rivero-de Aguilar, J., del Cerro, S., & Ruiz-de-Castañeda, R. (2009). Testing the use of a citronella-based repellent as an effective method to reduce the prevalence and abundance of biting flies in avian nests. Parasitology research, 104(5), 1233-1236.
Robyn is your friendly neighborhood writer, editor, and published author - boasting many years of experience in pest control, from which she magically weaves words into the captivating and engaging posts as we know them. When not tucked behind her laptop screen, she can be found embracing nature in the most thrilling ways possible. Rock climbing? Yes, please! Hiking? Absolutely! Traveling the U.S. with her husband, their lovable three-legged dog, and two mischievous cats? That’s her everyday reality. They live, love, and work in their cozy campervan, letting the road take them where it will, and finding inspiration in every sunrise, mountain peak, and wildlife sighting they encounter. Check out my Profile.
Pest Pointers was started in a cozy corner of Upstate New York, known for its expansive pastures, dense woods, and abundant wildlife pests. We are dedicated to providing YOU with solutions and insights into managing common pest issues. Starting out on over 50 acres of land and a freshwater bass pond with abundant pests, we combine firsthand experience with dedicated advice to help you tackle even the toughest of critters!
