Black bean louse: identify & control

Will the bean aphid affect your beans or ornamental plants? We explain how to prevent black lice and how to fight them successfully.

Aphids can be found in almost every garden, the black bean louse being particularly common. But the bean louse cannot only infect beans for a long time. We will show you how you can fight the black lice naturally and prevent them from re-infesting.

Recognize the black bean louse

The black bean louse (Aphis fabae) is one of the most common aphid species in gardens. The black bean louse does not only infect beans (Phaseoleae) for a long time. In addition to the particularly susceptible beans such as the field bean (Vicia faba) and other legumes (Leguminosae) such as peas (

Pisum sativum) beetroot (Beta vulgaris subsp. vulgaris), Swiss chard (Beta vulgaris subsp. vulgaris), Spinach (Spinacia oleracea), Asparagus (Asparagus), Dahlias (Dahlia) or Clematis infested by black aphids.

As the name suggests, the black bean aphid is black in color. In order to recognize an attack by aphids, for example the black bean louse, it is best to look at the shoot tips or flower buds of your plants. Here the black lice particularly like to suckle the sweet phloem sap of the plants. Symptoms that indicate an aphid infestation are deformed young leaves and shoots, leaves stuck together with honeydew and an increased occurrence of ants. So kick Ants and aphids often together. The ants target the sticky honeydew that the lice excrete when they suckle on the plant. They even protect the lice from predators. The honeydew also collects on leaves and can be colonized by sooty fungi (Capnodiales), which inhibits photosynthesis in plants.

Lifestyle and characteristics of the black bean louse

The black bean louse changes host plants in autumn and lays their eggs on what are known as winter hosts. The Ordinary Eauheater (Euonymus europaeus) or the common snowball (Viburnum opulus) are the winter hosts of the black bean louse. From March onwards, winged female lice hatch here and from April onwards they spread to summer farmers like beans and spinach. Once a host plant has been found, a single female can give birth to several offspring in one day without having to rely on fertilization by a male. Especially in dry and warm weather it can quickly lead to mass reproductions. From June or when a plant is threatened with danger or overpopulation, winged ones hatch again Aphids, which travel long distances and thus attack plants that are further away can. In autumn, the aphids seek refuge with the winter hosts and lay eggs there again, which last through the winter.

Fight black bean louse

Individual aphids are not a problem. However, if there are too few beneficial insects and dry and warm weather, mass reproductions can occur, and plants can be damaged by aphids. In order to control aphids, it is not strictly necessary that you can determine exactly which aphid species it is. We will show you how you can fight the black aphids successfully and naturally.

Fight black aphids biologically

Around Control aphids, a whole range of resources is available. We recommend that you refrain from using synthetic agents, as these pose a higher risk of harming beneficial insects or harming the user. Instead, there are very effective and environmentally friendly biological alternatives. Means based on are particularly effective against black aphids Neem. Neem oil comes from the seeds of the Indian neem tree and contains an active ingredient that enables aphids to be combated in a natural way.

Rapeseed oil-based agents are also available for combating aphids. However, these do not have a systemic effect, so they cannot be absorbed by the plant. Some products contain pyrethrins, which can be obtained from plants, but can still damage many different beneficial insects.

Home remedies for the black bean louse

In particular, a slight infestation by the black bean louse can be combated with home remedies. One of the most effective home remedies is soapy water made from 150 grams of soft soap dissolved in five liters of water. The soapy water can then be applied to the infested plant several times a day. Nettle broth can also be used against aphids. To do this, add 500 grams of fresh nettles to five liters of boiling water and let this brew cool down. With a spray bottle you can spray the strained brew onto the infested plants twice a day. You can find out more helpful home remedies in our special article Home remedies for aphids.

Beneficial insects against black aphids

Beneficial insects help in the garden, especially as natural opponents, to prevent mass reproduction. The targeted use of beneficial insects in the event of an attack by aphids is also possible. Beneficial organisms such as ladybird larvae or parasitic wasp eggs can be bought in special online shops. This targeted use is particularly effective in closed rooms, for example in the greenhouse or winter garden. More exciting tips too Beneficial organisms against aphids we have summarized for you in our special article.

Prevent black aphids

The influx of aphids is impossible to avoid. Sooner or later, as a garden owner, you will be confronted with the pests. But it is wise Winter hosts of aphids, such as the eucoat and the common snowball, should not be planted in the garden. Owners of near-natural gardens have a clear advantage when it comes to aphids, because a particularly natural garden offers many beneficial insects a home. A balanced ratio of aphids and their predators can prevent aphids from multiplying on a large scale. Some species of parasitic wasps and parasitic wasps in particular can be considered beneficial insects Ladybirds against aphids can be used. In order to prevent a strong infestation, we recommend that you promote beneficial insects in your garden in a targeted manner. In summer, an untouched flowerbed with native flowering plants and herbs is helpful in welcoming beneficial insects. Our Plantura beneficial insect magnet is a seed mixture that makes it easier for you to create such a flower meadow. In the cold season of the year, retreats such as a pile of bark or an insect hotel are ideal to help beneficial insects through the winter.

One adapted fertilization Your plants can also reduce the likelihood of aphid infestation. We recommend that you ensure that you have a good supply of potassium and that you refrain from using nitrogen-based fertilizers. This ensures strong plants that are less likely to be attacked by aphids. For example, a primarily organic fertilizer with a high potassium content is ours Plantura organic tomato fertilizer.

Avoiding overly dense stands is also helpful in growing vigorous plants and reducing aphids skipping in spring.

Tip: Aphids often appear more frequently in spring and are then displaced by beneficial insects in the further course of the year. It is therefore perfectly okay to tolerate a light infestation in spring or to combat it with home remedies and only react with pesticides if the infestation is more severe.

The queen of flowers, the rose, is particularly popular with aphids. In our special article about Aphids on roses we will give you tips on how to get rid of the nuisances again.