Study was conducted at the Thrace Agricultural Research Institute during 1990-91 for the purpose of finding answers to the question of what the effect of orobanclrc is on sunflowers planted at different dates. Sunflower varieties Türk-Ay-1, Vniimk-8931, sundak, and TR-259 were planted at 5 different dates with fields infested with Orobanche. The first appearance of Orobanche shoots on the soil surface was earlier at late planting dates compared to early planting dates. It was also observed that the number of Orobanche shoots per plant was fewer when sunflower planting was made late.