Abstract: Mixing horticultural plants with companion plants (CP) was proposed as an alternativemethod to control green peach aphid populations. Basil, lavender and rosemary were assessed asCP associated with pepper plants subjected to aphid infestation: i) on mesocosms in growthchambers and ii) in olfactometers. When pepper was associated with rosemary, lavender or basil,female fecundity was significantly reduced. In addition female flight was the most important inthe presence of rosemary compared to other CP. Olfactory tests revealed that basil plants had arepellent effect on aphids. Our results sustain the hypothesis that associating CP with horticulturalcrops may be useful in reducing aphid populations.