Pest expert reveals simple trick to keep wasps out of your garden – and warns they are most AGGRESSIVE in September

With the skies over the UK finally clearing up, you might be hoping to enjoy a last bit of al fresco dining over the weekend.

But if you do plan to make the most of the sunshine, experts have warned that wasps might ruin the fun.

After an abnormally warm spring and the hottest summer on record, wasps have experienced a ‘population explosion’ across the country.  ^[1]

To make matters worse, James Copley, Director of Copley Pest Control, says that the stinging insects are now at their most aggressive. 

Between August and early September, wasp queens stop laying eggs, and the nest starts to enter the end of its life cycle. 

As this happens, worker wasps’ normal food sources are cut off, and they begin to seek out easily accessible, carbohydrate-rich human foods.

Mr Copley says: ‘As natural food sources decline, worker wasps are under pressure to find food, which makes them more aggressive and more likely to sting you.’ 

Luckily, Mr Copley says there are some simple steps that you can take to avoid being stung during the last of this year’s good weather.  

If you plan to enjoy next week’s good weather with some outdoor dining, experts warn that wasps are now at their most aggressive. Here’s how you can keep them out of your garden (stock image) 

The paper bag decoy 

According to Mr Copley, one of the best ways to keep wasps out of your garden is to convince them that your home is already infested with the insects.

Mr Copley says: ‘Wasps are highly territorial and won’t build nests near existing colonies.

‘Hanging brown paper bags around your garden creates the illusion of rival nests, making wasps avoid the area completely.’

All you need to do is crumple a large paper bag, which you can buy online for as little as 16 pence, and place it where wasps normally gather.

If you have a tree or other structure where wasps might naturally build their nests, you can place the bag there.

‘Hanging brown paper bags around your garden creates the illusion of rival nests, making wasps avoid the area completely,’ says Mr Copley.

‘They see the shape from a distance and instinctively avoid what they perceive as another wasp’s territory.’

Wasps are very territorial, and if they see another wasp nest, they won’t come any closer. You can exploit this by hanging a brown paper bag where wasps normally gather. The insects will mistake the bag for a nest and not approach. Pictured: A giant wasp nest found in Lancashire

As an added bonus, this method will only scare off wasps without harming beneficial pollinators such as bees and hoverflies.

Decoy food stations 

If you can’t keep the wasps out entirely, the next best thing to do is keep them away from where you are eating.

To do this, Mr Copley suggests giving the wasps a ‘decoy food station’ as a distraction.

If you’re planning on hosting an outdoor dinner, Mr Copley says that ‘it may be best to place a small plate with sweet foods, such as jam or old fruit, at the far end of your garden before guests arrive.’

He adds: ‘Wasps will be attracted to this designated feeding station rather than bothering your gathering.

‘This simple diversion tactic draws on the natural food-seeking behaviour of wasps and diverts them away from you and your guests.’

This will be especially important as wasps enter the most aggressive phase of their life cycle in September.

Wasps are experiencing a ‘population explosion this year. In terms of scale, the wasps’ nests could grow as big as a space hopper, according to the expert. Pictured: a wasp nest found in Lancashire this year

Experts suggest leaving a decoy food station with sugary treats like jam somewhere away from where you plan to eat. This will lure the wasps away from you and help avoid stings (stock image)

Normally, wasp larvae produce a sugary liquid as they grow that feeds the worker wasps.^[2]

But towards the start of September, wasp queens have stopped laying more eggs, so no more larvae are born, and the workers’ food supply is shut off.

‘As worker wasps lose this food supply, their feeding behaviour changes and they tend to seek out carbohydrate-rich human foods that are easily accessible,’ says Mr Copley.

Natural deterrents 

Additionally, Mr Copley says that there are a number of natural and common ingredients that can be used to deter wasps.

One of the most effective measures is a mixture made of equal parts white vinegar and water.

Mr Copley recommends making a spray bottle with this mixture and applying it to surfaces once every few hours.

When applied to surfaces where food will be served, the mixture helps to drive wasps away.  

He says: ‘The acidic smell repels wasps, but leaves no lasting odour once it evaporates, making it perfect for food areas.’

Likewise, some food scraps which you might otherwise throw away can drive back an invading swarm of wasps.

Mr Copley says: ‘Fresh cucumber peels contain acidic compounds that wasps find unpleasant. 

‘Placing the peel around your garden, on picnics or outdoor seating areas, creates a natural barrier that wasps actively avoid.’

Just be sure to swap out the peels every few hours, since these will dry out in the sun and become ineffective. 

Alternatively, placing small bowls of used coffee grounds at strategic locations can help keep wasps away.

‘Coffee grounds produce a strong smell that masks the scent of food and confuses wasps. Simply collect your used grounds from morning coffee and place them in small containers around eating areas.’

Although wasps might be a nuisance, experts caution against using harsh chemicals or toxic wasp-killing sprays to deal with the problem.

Unlike the invasive Asian Hornet, wasps are beneficial to the ecosystem. Experts caution against using any harmful chemicals that could destroy their populations 

Despite their painful stings, wasps play a key role in garden ecosystems, and the UK’s biodiversity would suffer without them.^[3]

Wasps keep other insect populations in check, provide a source of food for many animals, and help to pollinate native flowers.

Chemical treatments can also enter the ecosystem and have damaging knock-on effects for more welcome species, such as bees and butterflies. 

Mr Copley says: ‘Wasp prevention is the most effective way of warding off wasps, especially when natural repellents are used, as these cause no harm.’