Aphids can weaken our plants so much that they die. We reveal which beneficial insects help against lice in the garden and how to use parasitic wasps, lacewing, and co specifically against aphids.
Aphids ( Aphidoidea ) are frequent but mostly uninvited guests in our gardens, greenhouses, or on the windowsill. The sapsuckers are only a few millimeters in size and colored green to black, depending on the species. While they feed on the phloem sap of the plant, they secrete so-called honeydew, which can be seen as a sticky, shiny coating on leaves. Another characteristic of the aphid is leaf curl and reduced growth of the plant as a result of sucking activity. We introduce you to the most important beneficial insects against aphids to take ecological action against aphids.
Which beneficial insects help against aphids?
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The parasitic wasp and ladybird are certainly the best-known representatives of beneficial insects that can be used against aphids. But lacewings and gall midges are also there to help if your plants are attacked by aphids. Beneficial insects can be acquired and settled specifically for plants in greenhouses, winter gardens, and indoor plants with aphids. In the open field, it is advisable to create habitats in which beneficial insects feel comfortable so that they migrate by themselves. Settling in the field is not that easy, as the beneficial insects often simply spread around the area and do not stay on the treated plant.
Parasitic wasps against aphids
Some parasitic wasps ( Ichneumonidae ) parasitize aphids, which is a very good option for natural control. The female lays eggs in aphid larvae or adult aphids and in this way suppresses its host, i.e. the plant pest.
Parasitic wasps can be used against aphids both outdoors and indoors. A female parasitic wasp can parasitize around 500 aphids in a short time. Here, the female lays an egg with her laying stinger in the aphid previously stunned by the parasitic wasp. The larva that hatches later from the egg then kills the louse. The parasitic wasp, which is a few millimeters in size, is completely harmless to plants and humans.
You can buy these beneficial insects against aphids in small containers on the Internet or in specialist shops. These containers are hung on the plant infected with aphids and the little helpers distribute themselves. The use of parasitic wasps is possible from a temperature of over 15 ° C. Before use, the aphid species should be determined or a mixture of different parasitic wasp species should be used.
A particular parasitic wasp species can only parasitize a few species of aphids. However, parasitic wasps providers will be happy to advise you on this. Parasitic wasps can also help against whiteflies, codling moths, and cabbage whiteflies. If you don’t want to do without the help of parasitic wasps outdoors, you have the option of offering living space in the form of wooden trunks with holes a few millimeters in size.
The insects, which are just a few millimeters in size, are completely harmless to humans but can be used extremely well against aphids
Here you will find the most important aphid species as well as the matching parasitic wasps:
|Aphid species:||Ichneumon wasp species:|
|Peach aphid ( Myzus persicae )||Aphidius colemani|
|Green cucumber louse ( Aphis gossypii )||Aphidius colemani|
|Potato aphid (Macrosiphum euphorbiae )||Aphidius matricariae|
|Black bean louse ( Aphis fabae )||Lysiphlebus testaceipes|
Ladybirds against aphids
The seven-point ladybird ( Coccinella septempunctata ) is known to many as a good luck charm – and it also helps us against aphids. The ladybird only feels at home outdoors. The adult animal also likes to eat aphids, but the three to nine millimeters large blue-black ladybird larvae are much more voracious. A single larva can devour up to 4000 aphids within two weeks. Thus, the use of ladybird larvae against aphids is well suited even in the case of a strong infestation.
You can order ladybird eggs in small containers on the Internet, which you then distribute on the infested plant in the evening or when the sky is cloudy. The voracious larvae soon hatch from the eggs at a temperature of 15 to 20 ° C. If you want to establish beneficial insects against aphids in your garden, you can encourage this through natural hedges and native plants such as the white goosefoot.
Lacewing against aphids
The larvae of lacewings ( Chrysoperla carnea ) are also known as “aphid lions” because of their hairy appearance and also like to eat aphids. Lacewing can be used against aphids outdoors and in the greenhouse. They grab the aphids with their suction tongs and suck them out. A lacewing larva can eat up to 800 aphids within two weeks. The beneficial insects against aphids can be used both outdoors and in greenhouses or living spaces.
Lacewing can be used at temperatures above 10 ° C. You can buy the larvae on the Internet embedded in corrugated cardboard and spread them on the infested plant with a light tap. The lacewing is the ideal beneficial insect if your plant is not only infested with aphids but also thrips or spider mites, as lacewing larvae are only too happy to eat them.
The lacewing feels particularly comfortable in your garden if you offer natural hedges and leave the autumn leaves to lie over winter. Lacewing can be specifically attracted with a red-painted lacewing box, in which they can find shelter at the same time.
Gall mosquitoes ( Aphidoletes aphidimyza ) are only suitable for use against aphids in greenhouses or living rooms. The gall mosquito larva numbs the pests and sucks them out. A larva can suck up to 80 aphids within a week. The earlier the beneficial insects are used against aphids, the more effectively they are reduced. It can be used at temperatures above 18 ° C between March and September. Occasional spraying of the plant with water also helps with the colonization of the gall mosquito larvae. The larvae and adult animals are completely harmless to both plants and humans. Gall mosquito pupae can be ordered online, from which the orange-colored larvae hatch. The pupae are placed on the ground under the infested plant.
Predatory mites against aphids
Predatory mites are ideal for combating an infestation by, for example, spider mites or thrips. However, if your plants are infested with aphids, the use of predatory mites will not be successful. Aphids are not on the menu of predatory mites, which is why we recommend the use of the beneficial insects presented so far.
This is how you fight aphids with beneficial insects
You can buy and settle some beneficial insects in the event of an acute infestation. But if you want to prevent pests such as aphids from multiplying too much, you should welcome and receive beneficial insects in the garden. You can do this with a flower meadow that not only looks very beautiful but also provides food for insects. Our Gardender beneficial insect magnet is a seed mix with over 20 different plants that will allow you to create such a meadow in no time at all.
Especially in summer, it can get very dry in our gardens, which can be a problem for the insects that live there. Insect drinkers can help here. A small bowl of water and small pieces of cork or wood floating on the surface of the water allows the insects to drink.
The use of only insect-friendly plant protection measures is also important. Small retreats such as piles of wood and bark or stems that have left withered shrubs also help to encourage beneficial insects in your garden. An insect hotel is also a good option – it gives the beneficial insects shelter and the opportunity to multiply. This way you not only keep pests at bay but also encourage insects that help pollinate your plants.
By the way: aphids are not only eaten by insects such as parasitic wasps, ladybirds, lacewings, and gall flies, but also by birds. These can also be specifically promoted as beneficial insects in the garden. Nest boxes in trees, hedges, or a quiet corner of your garden allow birds like the blue tit to nest. The parent animals will help you keep the pests under control.
Sometimes animal helpers can no longer contain the aphid infestation. In such cases, our Gardender organic pest-free neem helps. The 100% herbal remedy from the seeds of the neem tree helps reliably and naturally against pests such as aphids and Co.
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