This simple sugar solution will keep flies off houseplants – plus 7 other non-toxic methods plants experts say really work

Did you know that one of the easiest ways to keep flies away from houseplants involves using an ingredient you probably already have in your pantry?

A simple mixture of sugar and water is one of the best alternatives to homemade bug sprays – and according to experts, it really works.

To help you get the most out of this natural solution, we asked gardening experts for their tips on getting the sugar solution just right and where to place it to prevent bugs from harming your beloved indoor plants. We also asked for alternative, natural, non-toxic methods to keep pests at bay. Here are their top recommendations.

The sugar-water trap

'A sugar and water mix, or using sweet foods like squashed fruit and honey acts as a successful fly trap, luring flies away from your plants and into the solution,' explains Chris Bonnett from GardeningExpress.

To make an effective sugar-water mixture, combine half a cup of sugar with one cup of water in a saucepan over medium heat. Stir until the sugar has completely dissolved.

If you want to store this fly trap for ongoing use, allow the mixture to cool completely and pour it into a clean jar with an airtight lid, such as these Wreck canning jars from Amazon. This can be stored in the refrigerator for up to one month.

As for placement, Chris Bonnett advises, 'Place a pot of sugar water mixture near your houseplants. The sweet smell of the mixture will attract fruit flies and prevent them from heading toward your houseplants. Position the pot in a surrounding area that is close enough to lure the flies, but not so close that they miss the mixture and head straight for your plants.'

Chris Bonnett

Chris is the owner of Gardening Express. He is also the publisher of Garden Couture Magazine and an expert columnist in the Daily Express.

Other methods to keep flies away from houseplants

Here are some well-known and other, lesser-known ingenious home remedies to eliminate flies that are attracted to your houseplants.

1. Use fragrant houseplants that deter flies

'Using fragrant plants can irritate flies, keeping them away from your plants,' says Chris Bonnett. These odors overwhelm the pests’ sensory systems, making it difficult for them to locate their preferred plants, food, or lay eggs near them making them an effective, natural deterrent.

By placing these nice-smelling scents that pests hate near vulnerable houseplants, you create a natural barrier that deters flies and helps protect your plants from infestations.

So what are some of the best fly repellent plants?

Basil is one of the most effective plants thanks to its strong scent, which contains limonene and citronella – both of which are known to interfere with a fly’s ability to detect food. Lavender also has a powerful aroma that disrupts flies.

Placing dried lavender bunches (such as these Tripumer dried lavender bundles from Walmart) or DIY lavender sachets near your plants can deter flies from approaching. Additionally, mint and rosemary are excellent alternatives, as their strong fragrances are equally effective at keeping flies away.

2. Use essential oils

'Essential oils are another great way to use scent to deter flies,' says Chris Bonnett. 'Adding a few drops of essential oils like peppermint, eucalyptus, or tea tree oil to the soil can help keep flies at bay by masking the scents that attract them.' This essential oils set from Amazon includes fragrances to repel flies from plants.

'Just remember to dilute the solution first to avoid harming your houseplants,' Warns Chris. The ideal ratio is ten to fifteen drops of essential oil per one cup of water. For extra effectiveness, you can add a teaspoon of liquid soap to help the mixture adhere to plant surfaces.

Consider using a spray bottle, such as these mister spray bottles from Amazon, for easy application. Simply mist the solution over the soil and around the plant leaves, avoiding excessive saturation. Reapply this every few days or whenever the scent fades.

3. Set up sticky traps

'Yellow sticky traps are great for catching adult flies,' says Eli Harel, partner and outreach specialist at Lice Busters. 'The bright color draws them in and traps them with their sticky surface.'

These are also non-toxic and are safe to have around your kids and pets.

Chris Bonnett advises: 'Place the sticky pads near your plants, position them close to the soil or plant stems. Avoid placing them directly on the soil to prevent disturbing the plant roots.'

These Visland 30 yellow sticky traps from Walmart come in a range of fun shapes to protect and accessorize your houseplants.

Eli Harel

Eli Harel is a seasoned Outreach Specialist at Lice Busters, based in New York. His dedication to community wellness and public education, combined with his background as a veteran, fuels his drive to offer reliable and effective services to every family in need. 

4. Add a layer of coarse grit

A layer of coarse grit placed on top of the soil forms a barrier that helps deter flies, particularly fungus gnats, from laying eggs in the moist soil.

In particular, materials like gravel and sand – such as this Triani coarse sand from Walmart – are excellent non-toxic pest control essentials. They not only discourage flies but also help to regulate soil moisture levels, preventing oversaturation that attracts them. The sand layer specifically prevents larvae from developing in the soil.

5. Introduce natural predators

To tackle the issue of fly larvae in the soil, Eli Harel recommends, 'Beneficial nematodes (tiny, harmless worms) can be added to the soil. They’ll hunt down and kill fly larvae. Another option? Hypoaspis mites, which love to feast on gnat larvae.'

These predators address the problem at its source, providing an efficient and natural pest control method. You can source both nematodes from Walmart.

6. Spray neem oil

Using neem oil on plants is an effective natural insecticide.

When mixed with water and sprayed on both the soil and leaves, it disrupts the entire life cycle of flies – from egg to adult – helping to prevent future infestations. Reapply weekly until the pests are eliminated.

7. Sprinkle cinnamon on the soil

Looking for another solution to your pest problem that you probably already have in your pantry? Chris Bonnett recommends, ‘Sprinkling a layer of cinnamon on top of the soil can help kill any fungi that may have developed due to excess moisture and humidity.

Using cinnamon on soil also acts as a deterrent for fungus gnats, preventing them from being attracted to the soil.’

FAQs

Why do flies gather around houseplants?

'Bringing greenery into your space is a great way to brighten up a room and create a refreshing atmosphere, but if you’re not careful, houseplants can attract flies,' says Chris Bonnett from GardeningExpress. 'This tends to happen if the soil is moist. Flies, particularly fungus gnats, lay their eggs in soil that has been overwatered and has become damp.'

Poor drainage and decaying plant matter only worsen the problem, providing an ideal environment for fungal growth and a breeding ground for them. 'Overusing fertilisers can lead to fungal growth, which also attracts gnats too,' adds Chris.

Once flies and gnats appear, they can be difficult to eliminate and will quickly spread to other houseplants, so prevention is key. Before tackling an infestation, the first step to get rid of fungus gnats and flies is to avoid overwatering and remove decaying leaves and debris, as these attract flies. Flies lay their eggs in damp soil, so allowing the top inch of soil to dry out before watering again can significantly reduce their numbers, as cutting off the fly’s breeding grounds makes it much harder for them to thrive.

Which plants are vulnerable to flies?

Certain plants are more vulnerable to fly infestations, especially if they provide a suitable environment for pests to lay eggs or feed.

Houseflies are drawn to decaying matter, overly moist soil, and decomposing leaves. They are most likely to infest herbs if they are overwatered, cacti and succulents if they are rotting, and orchids as they often have decomposing bark in the soil mix.

Fungus gnats thrive in damp soil and feed on organic matter and plant roots. Their common targets include peace lilies, snake plants, ferns, spider plants, and African violets.

Whiteflies feed on sap and target soft-leaved plants – such as jade plants, tomato plants, ficus, begonias, and hibiscus – weakening them over time.

To contain infestations and prevent them from spreading, it’s important to separate plants that have not been infested from those that are infected, as pests tend to lay eggs and spread quickly.

Andrew Levi CEO of PlantTAGG, also recommends, 'If the problem cannot be contained or is very bad, the best solution is to take all infected houseplants outside and repot them using high-quality houseplant soil which is certified free from pests and larvae. You will need to wash the roots of the plant well during the re-potting process.'

Andrew Levi

Andrew is the founder and CEO of PlantTAGG, Inc. based in Dallas Texas. PlantTAGG is the worlds smartest mobile gardening platform designed to significantly improve the outcome of residential gardeners of all skill levels. Built with cutting edge data science, AI/ML and world class data sources, our gardener users and garden center retailer partners are realizing our vision for "Taking the Guesswork out of Gardening" through PlantTAGG's in-store, at-home (mobile app), and online user expereinces.