No one wants a wasp nest in their garden or on their house. Before it gets to that point, you can take measures to prevent the nest building at an early stage. We show you what to look out for.

Many people consider wasps to be annoying insects, but the animals do have a benefit: The menu of wasps includes mosquitoes. A small colony of wasps eats up to 3,000 mosquitoes per day. However, there are of course reasons why you should prevent a wasp nest in your garden or on your house: First and foremost is the risk of an allergic reaction to a wasp sting. Also, the protection of your children speaks for a wasp-free garden. Wasp nests can also cause damage to your home or be home to particularly aggressive wasp species. In these cases, you should prevent the wasp nest or have an existing one removed.

Why do wasps build nests on houses?

Depending on the wasp species, the insects choose cavities, dense hedge plants, holes in the ground or tree tops as nesting sites. There they not only find protection from enemies, but also sufficient building material. The wasps need wood fibers from loose bark to build their nests, and deadwood is an abundant source of this material. They find it on fences, boarding and walls, which is why the animals usually settle on wooden structures. Wasps even find a suitable place in attics. They get in through gaps in windows and doors, as well as unsealed places. Another location advantage for a nest in the house is protection from wind and weather. Nests are often found in roller shutter boxes, bird nesting boxes, in the attic, in garden sheds, sheds, crevices on the facade, dense bushes and on garden furniture.

When do wasps build their nests?

Wasps begin building their nests in the spring. From the beginning of April, the queen wasp goes in search of a suitable nest site and starts building directly. The first larvae hatch from mid-May to mid-June and are adult workers after about four weeks. From the beginning of August, activity in the wasp colony subsides and preparations for winter begin.

How to prevent a wasp nest

  • Tip 1: Eliminate potential building material and food sources

Dead wood attracts wasps because they use the material to build their nest. Therefore, remove dead wood and dispose of it properly. However, you should be aware that you are also taking away an important nesting opportunity for beneficial bees and other insects.

While you’re already on the lookout for potential wasp building material, look for potential food sources as well. Wasps feed not only on nectar, but also on other insects such as caterpillars and worms. They usually find these in compost, so you should protect it with a lid to make it harder for wasps to get in.

Anyone who has had breakfast outside knows that wasps like to go for sweet foods like jam or cakes. Therefore, don’t leave these out in the open – this also applies to drinks. If you have fruit trees in your garden, protect them with a suitable insect net. Fallen fruit in late summer also attracts wasps.

  • Tip 2: Close off entrances

Even a small gap or crack in the masonry is an invitation for wasps to nest in your home. Many wasp species settle in shutter boxes because they are particularly dark and well protected. The insects get in through gaps between the window and the shutter. Install a brush seal to close off access. If you discover large cracks on your facade, it is advisable to seal them, and not just because of the wasps. Once the animals have taken hold, they can even eat their way through the walls. Also check your attic for leaks or porous insulation material as well as hollow tree trunks in your garden. These provide good nesting conditions for the insects.

  • Tip 3: Prevent wasp nests with odors

Wasps have a fine sense of smell. Take advantage of this and use certain scents to prevent them from building nests. For example, the insects cannot stand essential oils, which is why you should rub possible nesting sites with basil, lavender or clove oil or distribute appropriate scented sachets there. Strong scents also help to drive away wasps: for example, plants such as garlic, incense or onions should prevent the insects from settling.

Prevent reintroduction

If you discover an abandoned wasp nest, you do not have to remove it. As a rule, insects do not return to old nests. However, you should think about getting rid of it. The reason again lies in the smells: When looking for a nesting site, the queen perceives the smell of conspecifics. After all, the location seems to have been good for a nest last year. Therefore, it may well happen that a new swarm of wasps builds its home nearby. If you have the wasp nest removed, be sure to thoroughly clean the site as well, so that the smell of the old wasps fades away and does not attract new colonies.