Wireworms may look inconspicuous, but they can inflict tremendous damage. In the event of an infestation, quick action is required.
The click beetle is out and about in many gardens. There is no reason to worry, because the beetles are harmless and feed on nectar and pollen. The larvae of the click beetle, on the other hand, are extremely voracious and can cause damage to the vegetable garden. The wireworm lives in the soil and infests various vegetables. Wireworms love moisture and often burrow into ripe potatoes. The hobby gardener can take specific measures against the larvae of the click beetle and take preventive measures.
Detect Wireworms
The wireworm reaches a size of two to three centimetres. The most striking feature of the slender larvae is a hard, yellow chitinous shell, which completely encloses them and is also responsible for the unusual name of the pest. The wireworm has three pairs of legs, which are used for locomotion. Furthermore, the worm has a strong jaw and small pinpoint eyes.
After pupating, the wireworm develops into the harmless click beetle already mentioned. This is about an inch tall and brown to black in color.
Where is the wireworm found?
Farmland and vegetable patches are the primary habitat of the wireworm. Beds that have only just been laid out and were originally grassland are particularly at risk.
The preferred food for the wireworm is plants with soft roots.
The following species are endangered in the vegetable patch:
- Potatoes
- Tomatoes
- Salad
- Beetroot
- Carrots
- Peas
- Asparagus
Even soft flower bulbs are not spared by the larvae. The appearance of wireworms on indoor plants is also not uncommon. Commercial potting soil often already contains eggs or larvae.
Tip: If potting soil is sterilized in the oven or microwave before use, it can be kept germ-free.
How to recognize a wireworm infestation?
Since the wireworm lives in the soil, it is free from infestationnothing to see at first. Affected plants wither rapidly. The hobby gardener can often easily pull the stems out of the ground because the roots have almost completely been eaten away. An infestation often results in the death of the plant.
On closer inspection, feeding tunnels can be identified in the vegetables. The wireworm leaves round boreholes in potatoes or carrots. There are hardly any root remains.
Can potatoes with wireworm be eaten?
Wireworms cork up the tunnels they have drilled into the potato. Feces accumulate in the drill holes. Bacteria and fungi can enter the boreholes and lead to secondary infections. In this case, the gears are discolored black. You should no longer serve vegetables that have been infected in this way.
Tip: You can cut out slight damage caused by eating and continue to eat the vegetables.
Fighting wireworms - the best tips
The infestation with wireworms does not have to be accepted. There are a few ways to specifically combat wireworms or to greatly reduce their infestation.
Wireworms and pesticides
No chemical pesticides against wireworms are currently (as of 2022) commercially available. Consequently, other solutions must be sought. Attempts are currently underway to kill wireworms using the soil fungus Metarhizium.
Destroy wireworms through targeted tillage
The wireworm loves it wet. If the larvae are in the upper soil layers, the soil should be thoroughly raked. Choose a sunny and dry day for this.
If you dig up the ground, the worms will reach the upper layers of the earth and can be collected from there by hand. Free-ranging chickens are happy to do this work for you.
Fighting Wireworms with Predators
The wireworm has a number of other natural predators:
- parasitic wasps
- Beetle
- Shrews
- Hedgehog
- Moles
- crows
- Stare
Trap the Wireworm
Hobby gardeners can become trappers for natural control of wireworms. You can easily make the traps yourself. All you need are simple wooden skewers and several wide potato slices.
The potato slices are placed on the wooden skewers and the bait is dug about two inches into the ground between the endangered vegetables. Toa few hours the wireworms should have accepted the bait. Then the skewers can be pulled out of the ground again. You can put bait and worms in a bucket and empty the bucket where the pests can't wreak havoc.
To effectively combat wireworm, make new baits and repeat the process.
Use targeted plants against wireworms
Some plants don't get wireworm. These include marigolds and marigolds. If the flowering plants are placed between the vegetables, the infestation can be significantly reduced. The roots are poisonous to the larvae and they die immediately on contact.
Decimate Wireworm Infestations by Fertilization
If the bed has been prepared for planting, it should be fertilized with calcium cyanamide. About a week after treatment with this fertilizer, you can sow as usual.
Tip: Fertilizing with calcium cyanamide can reduce wireworm infestations in the vegetable garden by up to a third.
Prevent wireworm infestation - this is how it works
Infestation can be prevented with various methods. For example, if a piece of lawn has been turned into a bed, none of the vegetables mentioned should be cultivated there for the first two years.
1 Frequent loosening of the soil can also help against wireworms. The hobby gardener should keep an eye on his plants and check whether there are any signs of damage or general signs of illness.
2 He althy and vigorous plants are best protected against diseases and pests. This also applies to vegetable plants. If you grow your own plants, you should only plant them out when they are strong enough. Cultivation on the windowsill can begin in late winter.
Tip: Potatoes should be pre-germinated before planting.
3 The wireworm will prefer to visit the potato patch. The hobby gardener can thwart these plans with an early potato harvest. When buying, look for early-ripening varieties. These potatoes can be harvested in early summer and the wireworm does not get the opportunity to burrow its burrows into the potatoes that are ready for harvest.