Grubs are the larvae of scarab beetles. This type of beetle includes the May and June beetle as well as the rose beetle. The pests include the offspring of May and June beetles, while the larvae of the rose chafer are referred to as "harmful beneficial insects". Since the grubs feed on the roots of the plants, they are enemies of hobby gardeners and should be removed as soon as possible if infested. But how to fight them?
grubs
distinguish
Engerling is not the same as Engerling. In addition to their appearance, the larvae can also be easily identified by their escape behavior if they are placed on a flat surface.
May and June beetle grubs escape in a lateral position or on the stomach. They are the same thickness at the back and front.
rose chafer grubs roll onto their backs and then crawl like a caterpillar. They are significantly thicker at the back than at the front.
Tip: If you find a grub in the compost heap, it is a rose grub. As a useful pest, it loosens the compost heap. The larvae of May and June beetles do not colonize compost heaps.
grubs in the ground
preventive measures
So that you don't have to kill beetle larvae, you can ensure that the beetles are kept out of the garden and do not lay eggs in the garden from which the larvae hatch in the first place. The simplest ways to protect the raised bed from the pests are the following.
- a dark garden
- loose earth
Dark Garden
With a little light in the garden, for example from solar lamps, wonderful effects can be achieved in the dark. However, the light sources also attract the beetles because they lay their eggs near the light sources. You should therefore avoid these effects in May and June, i.e. at the time of shedding, and keep the garden dark.
Tip: If the light source is a street lamp, you should protect the raised bed with an insect screen.
loose earth
The beetle larvae need 100 percent humidity for their development. Therefore, they prefer poorly tilled soils. In order to deprive the pests of their preferred habitat, the soil should be worked regularly, especially at the time when the eggs are laid. In addition to digging, this preventive measure also includes other soil work, such as weeding or raking.
fight grubs
If you discover an infestation by the pests, you should act immediately. Because to protect the plants, you need to get rid of the beetle larvae. However, before you resort to chemical mace, you should rely on gentler methods, such as collecting the pests.
Collect
In order for the grubs to be collected, they must first be transported to the surface of the earth. In the raised bed, this is best done by digging.
Raised bed in the garden
Tip: If possible, make sure that the plants or their roots are not damaged when digging up.
Not only does digging bring the pests to the surface, it also loosens the soil, which they don't like at all, and they then come up on their own.
Alternatively, you can also fight the pests with water. Beetle larvae burrow to the surface after heavy rain. If the rain fails, you can also flood the soil heavily.
Tip: In the raised bed, you should make sure that the plants can also tolerate being washed with water.
Once the pests are on the surface, you can easily collect them. Once collected, the pests do not necessarily have to be killed, because the beetles have also become rare. You should therefore release the grubs in a meadow far away from your own garden.
Natural predators
White grubs are on the menu of various animals. Some of the natural predators that will help you get rid of the pests include those listed below.
hedgehog in the garden
- Birds, especially blackbirds, love grubs
- mice
- Hedgehog
- moles
- marten
- bats
- Big ground beetles
In order to attract the natural predators, you should provide appropriate quarters and nesting sites. But small delicacies and/or fodder plants also attract the animals.
blackbird
Tip: The pests are often eaten by birds after heavy rain. With a bit of luck they don't have to be collected at all.
plants to combat
In the vegetable patch, garlic deters beetles. It is best to put the garlic between the other plants. In the flower bed, delphiniums or geraniums help against the pests, as their roots are also eaten by the grubs. However, these plants contain a deadly poison for the beetle larvae.
kill grubs
Gathering grubs is not for everyone, nor can it be guaranteed that the predators of grubs will actually settle. Nevertheless, you have to get rid of the pests. One possibility are nematodes, because they kill the grubs.
grubs in the garden soil
Nematodes are tiny roundworms that cannot be seen with the naked eye. You can get them in specialist shops or order them online. You can get nematodes in clay granules that are put into the irrigation water. This is how the nematodes get into the soil when watering. If they have found a grub, they enter the vermin and it is killed.
insecticides
The chemical mace should be the last resort to fight the beetle larvae. Because their use always means that beneficial insects also die. In addition, the contained toxins, if they are used in crops, ultimately end up in your own body through consumption.