Aphids are a very common insect which sucks out the sap of your plants, which can cause plants to not grow as well as they might. They can leave a sticky substance behind, called honeydew. This secretion sticks to the leaves of the affected plants and can allow te growth of sooty mould. Some aphids can transmit viruses to your plants, particularly problematic for strawberries, raspberries, tomatoes, cucumber, tulips and sweet peas. There are known to be more than 500 different species of aphid in the UK!
There are numerous ways to combat aphids, some which are chemical based and some which are more natural. For gardeners who opt for fully organic growth, natural solutions will be the better choice.
Aphids have a lot of natural predators, such as the ladybird, hoverfly larvae, lacewing larvae and parasitic wasps. The problem with using other insects as your primary way to get rid of aphids is that the aphids tend to do most of their damage in the spring before the predator numbers have increased sufficiently.
During a growing season, there are lots of different insecticides which can be used to get rid of aphids. You need to be able to spray a plant thoroughly, so taller or larger plants are going to be very difficult to effectively treat. Make sure you read the label on any pesticides. Do not spray any plants which are in flower, as this can be a danger to valuable pollinating insects.