Small, fat, round insects that generally congregate around the tips and new shoots of plants. The leaves are often sticky from the honeydew that the aphids secrete.
Harm
Bad infestations can reduce the vigour of a plant and leave it vulnerable to attack by other pests and diseases. Virus diseases can be spread by aphids as they move from one infected plant to another. Aphids feed by sticking their mouth parts straight into the plants veins. Any excess sap they cannot consume simply spills out around them. This is why leaves often feel sticky. This sap is often colonised by black sooty mould which can smother the upper surfaces of the leaves and reduces the plants ability to make food.
Treatment
Organic – if possible, the best thing to do is put your houseplant outside for a spell in the summer when the weather is very warm. There are lots aphid, such as ladybirds, lacewings and hoverflies, in the garden that should make short work of the infestation. There are also organic insecticide sprays like Natures Answers.
Chemical – insecticidal pins which are sticks impregnated with an insecticide and pushed into the compost are a simple, easy way of tackling pests indoors. The chemical is systemic so is taken up by the roots of the plant and carried around to all parts of the plant. There are other sprays available but make sure the room is well ventilated when using them as they are very toxic.
