In fact, these are not real fleas, but rather tiny bugs that are only a few millimeters in size. They owe their name to their powerful hind legs, which they use to jump from leaf to leaf, just like real fleas. Their diet includes not only the young leaves of ground-level vegetables from the cruciferous family, but also nightshades such as tomatoes and potatoes, aubergines and peppers. The bad news is that there are no approved pesticides for home use to control flea beetles. The good news is: With the right measures, you can stop the infestation and prevent damage caused by feeding.
The beetles, which are two to four millimeters in size, can differ from one another visually: potato flea beetles have a rather dark brown shell with yellow vertical stripes and prefer nightshade plants. Rape beetles, on the other hand, have a blue-black to dark green shimmering shell and prefer to eat the young plants of cruciferous plants such as rocket. The resulting holes on the leaves are small and round, but the edges remain undamaged. This is how the typical window damage occurs - a clear sign that your vegetables have been infested with flea beetles.
Depending on the weather conditions, flea beetles can go through one to two generations per gardening season. In the spring, the females begin to lay their eggs in the soil of your vegetable beds. The larvae then feed on the roots for a few weeks without noticeably harming the plants and pupate. The beetles that hatch between June and August, on the other hand, have a big appetite and attack all young plants near the ground. Only in autumn, when it gets colder, do the flea beetles look for winter quarters - usually in the ground or under dead plant compost.
As already mentioned, there are currently (still) no commercially available pesticides that are approved for private use. You can still take sensible measures to control flea beetles. These include the following:
You can take preventive measures to ensure that the ravenous beetles don't even start tampering with your vegetables - for example by sowing all sprouts and seedlings early, provided the weather conditions are right. This allows your young plants to outgrow the critical period of a possible infestation more quickly. As a result, it is all the more important to provide your vegetable beds with the best possible care: with nutrients (e.g. fresh compost soil) that stimulate growth. In addition, you can protect your beds in the spring with a fine-meshed net.
To combat flea beetles, you can also encourage their natural predators such as hedgehogs in the garden - with suitable accommodation such as piles of leaves, stacks of dead wood or a special hedgehog house. Alternatively, leaf beetles have their eye on flea beetles: these nocturnal animals prefer to hide under stones or wood during the day, provided there are enough of them in your garden. Or you can take an old clay pot, fill it with straw and hang it upside down. This allows the leaf beetle to hide in it during the day and hunt the flea beetle at night.
Source: "My beautiful garden"
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