Wasps in the garden: Why they are active now and how to react

Key points at a glance

• The apparent plague in July is a natural effect of the continuous growth of a wasp colony since spring.
• Only the common wasp (Vespula vulgaris) and the German wasp (Vespula germanica) are interested in human food.
• Wasps are ecologically indispensable beneficial insects as they hunt other insects and act as pollinators.
• Keep your distance rather than fighting them: avoid frantic movements in the immediate vicinity of the nest.

Why wasps seem omnipresent in high summer

If you suddenly notice more wasps on flowers or fallen fruit in your garden, this is not a sign of overpopulation, but proof of a healthy biological system. A wasp colony is established in the spring by a single queen that has survived the winter. Initially, she performs all tasks alone – from building the nest to caring for the first larvae. It is only when the first generation of workers hatches that the colony grows exponentially.

In July, this growth reaches its peak. Thousands of individuals – the common wasp (Vespula vulgaris) and the German wasp (Vespula germanica) can have thousands per nest – are now flying outside the nest at the same time. Because the workers are constantly commuting between food sources and the nest, you will encounter these insects much more frequently now than in May or June.

Ecological function: Hunters and pollinators

Wasps perform important functions in your garden. The adult insects require sugary substances like nectar or honeydew to generate their own energy. When hunting for the proteins they need to feed their larvae, they catch a large number of insects such as flies or small caterpillars. In doing so, they act as a regulator for insect populations and also contribute actively to pollination by consuming nectar from flowering plants and transferring pollen.

Why some wasps come to the dining table

The interest in our food usually only appears in late summer. During the peak phase of nest building, the workers receive sugary secretions from the larvae in return for providing them with protein. As brood activity wanes towards the end of the summer, this energy source disappears. The workers then increasingly search for alternatives such as sugary foods or ripe fruit.

How to behave correctly

1. Keep calm: Individual wasps foraging for food are not aggressive if approached normally. Avoid frantic defensive movements, as these can be perceived as a threat.
2. Keep your distance: The immediate area around a nest should be left undisturbed. Avoid vibrations or blocking the entrance, as social wasps defend their nest against perceived threats.
3. Manage food sources: Cover sweet foods when outdoors and clear away fallen fruit promptly so as not to attract the insects unnecessarily.
4. Acceptance: View the animals as part of the local biodiversity that relies on their energetic food sources.

Frequently asked questions

Are wasps generally aggressive?

No. Individual wasps searching for food only defend themselves if they are harassed. Aggressiveness usually only occurs in the immediate vicinity of the nest if it is disturbed.

Why do only some wasps come to the table?

Only the common wasp and the German wasp have a preference for our food. Most other species are not interested in the dining table.