Managing aphids in the garden:

Aphids in moderation are good. They are easy to deal with using integrated pest management. The damage done by aphids to plants is directly related to the number of aphids feeding on said plant. If the numbers are kept low the damage will be minimal.

If there are aphids around; ladybugs and parasitic wasps will follow. In fact one can be alerted to an aphid infestation by the increased number of ladybugs. The aphids are less obvious, they tend to look like the plant they are on and they hang around in the tender new growth where leaves are small and tight and little bugs are harder to see. If an aphid is swollen and darker than his mates he may be harboring the young of the Encarsia Wasp. Those not parasitized are often they are the same color as the plant. They line up in symmetrical little lines and just look like the branch tip. Once the ladybugs arrive they will eat prodigious numbers of the little guys. Ladybugs are great to have around to those gardeners with anthropomorphic tendencies. We think they are cute little friends when really they are big time hunters. So…. back to aphids, if we use integrated pest management we will control the aphid population but not eliminate it. Hence we still get ladybugs and ladybugs are fun. Imported (or purchased) ladybugs tend to fly away to territories with more aphids.

Also, aphids make great food for aquarium fish. One can shake the tender and therefore flexible new growth tips of the plant over a container and off fall the aphids. A few will fly away to start the next aphid population explosion but many will be wingless and of varying sizes and will fall into the container in a big pile suitable for feeding as live food or for freezing in little aphid ice cubes for use later. Either way the fish love them and it helps to condition the fish for breeding. A little bonus for the non-pesticide user.

If the population is too big and the plant is being damaged a strong spray of water will knock aphids right off and kill most of them as they have very soft bodies and squish easily. Many of the plants aphids prefer need trimming of new growth tips anyway. Pruned tips can be thrown away, aphids and all. Eventually as the new growth hardens and the season progresses the aphid population decreases to more manageable numbers. Tem42 explains this well in the write up above on the aphid life cycle.