If flies and mosquitoes have been plaguing your patio this summer, pest experts have revealed how a mix of coffee grounds and bicarbonate of soda can deter them from your garden, leaving you free to host, relax and enjoy.

It’s always helpful to know how to get rid of flies and mosquitoes. These buzzing pests can be a real nuisance when trying to enjoy your garden, and in the case of mosquitoes, carry a nasty bite, too.

Recently, Ideal Home’s Cleaning Editor Lauren Bradbury used coffee grounds to deter flies from her home, and now pest experts have revealed you can apply a similar principle to your patio. Here’s how.

What’s the hack?

Coffee has a strong fragrance that flies and mosquitoes can’t stand, and once lit and smouldering, they won’t go anywhere near it.

‘Flies and mosquitoes locate food and hosts primarily by smell, and strong, unfamiliar odours confuse and deter them. Coffee grounds produce a powerful, bitter aroma that insects find deeply unpleasant and that masks the smells that attract them in the first place, such as food, sweet drinks and carbon dioxide from humans,’ explains Mosh Latifi, Co-Owner, EcoCare Pest Management.

‘Bicarbonate of soda used as part of a mixture can produce carbon dioxide when combined with an acid, which confuses mosquitoes whose tracking systems are tuned to follow CO2 towards a host. Used together, they create a reasonably effective scent barrier around a patio.’

Many pests, including flies and mosquitoes, rely on scent to navigate and communicate, and so scent deterrents are an effective way to keep them at bay. This scent deterrent method is easy to follow, too. Burn dry coffee grounds in a heatproof dish on your patio, and pests will stay away.

‘Sprinkle bicarbonate of soda in and around rubbish bins or in areas where food odours tend to linger,’ suggests Daniel Steward, Managing Director at Shield Pest Control.

‘Before using coffee grounds, ensure they are completely dry. Place them in a heatproof container outdoors and light them so they smoulder rather than burn with a flame. Position the container near seating areas, while keeping it well away from flammable materials.

‘These natural methods work best alongside good patio hygiene. Regularly empty rubbish bins, wipe away food and drink spills promptly, remove fallen fruit, and eliminate standing water from pots, buckets, and other containers to prevent attractive odours and mosquito breeding sites from developing.’

Is this a good hack to use?

While it definitely works, this method is most effective when the coffee is burning. So, unless you’re a full-blown coffee addict and have a steady supply, or have one of the best coffee machines at your fingertips, you might need a more permanent solution.

‘The benefits last only while the bicarbonate of soda continues to absorb odours and the coffee grounds are still smouldering. Once the smoke dissipates or new odours develop, flies and mosquitoes are likely to return,’ confirms Daniel.

However, this doesn’t mean the method is without benefit; it should be used alongside other deterrents.

‘It is a reasonable first line of defence for casual outdoor use and has the advantage of being cheap, natural and widely available. It will not replace a citronella candle or a pheromone trap for serious mosquito pressure, but as a supplementary measure around a patio table, it is worth doing. The burning coffee grounds method in particular is something I genuinely recommend for evening use outdoors when mosquito activity peaks,’ says Mosh.

Don’t let pests put you off enjoying your patio this summer. Employing the right deterrents means you can have a practically pest-free summer.