Regular checks: Prevention makes fighting easier
During the summer, aphids can multiply surprisingly quickly due to their rapid generation sequence. Therefore, you should gently push apart the dense foliage of hanging petunias with your hands at least once a week to check the shoots for attached lice. A slight infestation with aphids is quite natural and does not necessarily have to be a problem. However, aphids can also transmit viral diseases that may even kill the petunias.
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- Watering petunias properly
Home remedies for aphid infestation of petunias
A sharp jet of water is usually enough to rinse off a certain part of the aphids sitting on the shoots and thus make it more difficult for them to succeed in generations and spread. There are several home remedies that have been shown to be effective in controlling lice on the petunias:
- Tobacco solution
- Injections made from water and soft soap or detergent
- Stinging nettle manure
- Coffee grounds
While the coffee grounds are spread out directly on the plant substrate in the pot, the floor should be covered when spraying the plants with the liquid household remedies. A biological alternative can be the purchase of beneficial insects such as ladybirds from specialist retailers, as long as they are the native species of ladybirds in this country.
Long-term control of aphids in the garden
Plants such as nasturtiums, elderberries, roses, daisies and petunias are a magical attraction for aphids. If you are growing many of the plants mentioned in your garden, you should always keep an eye on the pressure of aphids. In the long term, you can minimize the care required by the lice if you encourage the colonization of natural predators of aphids such as ladybugs and parasitic wasps (€ 14.59 on Amazon *). Offer ladybirds and other beneficial insects a suitable habitat with an insect hotel (€ 8.87 on Amazon *) and they will take care of the aphid plague for you. Since ants create and maintain real “plantations” of aphids due to the popular honeydew, ant nests should be removed from the window boxes (€ 106.25 at Amazon *) with petunias.
There are various chemical agents commercially available for combating aphids, with systemic agents being preferable in case of doubt. These are stuck into the substrate around the petunias as sticks, for example, so that the toxins they contain are absorbed by the plants. As a result, aphids sucking on the sap quickly die without the ambient air being polluted with an agent sprayed on the plants.