Both adults and nymphs suck plant sap, which usually causes distorted leaves, buds, branch tips, and flowers. Severely infested leaves and flowers may drop. As they feed, aphids excrete a sweet, sticky honeydew onto the leaves below. This allows a sooty mold to grow, which, in addition to being ugly to look at, blocks light from leaves. Also, some aphids spread viruses as they feed.
Organic Control :
- Drench the plants with strong sprays of water from a garden hose to kill aphids. (A hard, driving rainstorm will have the same effect.)
- Keep your plants as healthy as possible, and spray dormant oil to control overwintering eggs on fruit trees.
- Control ants that guard aphid colonies in trees from predators by placing sticky bands around the trunks.
- Spray aphids with insecticidal soap, summer oil (on tolerant plants), and homemade garlic sprays.