Stop aphids killing your plants Aphids: Control with Lacewing Larvae Aphids suck the sap weakening plants, foliage may discolour & drop. Aphids produce a sticky deposit honeydew which later goes black on plants, they also transmit plant viruses. Control with Lacewing Larvae (Chrysopa Carnea): Aphids are the favourite diet of Lacewing Larvae. In addition they will feed on other small insects such as thrips, red spider mite & mealy bugs. Can be used inside or outside, introduce when aphids first seen. Having trouble with garden pests? These biological control products will ensure that pests stop killing your plants.