Abstract: By analyzing the change rules of the soil moisture content of sunflower in whole growth period using ten years observation data of soil moisture,it showed that there were three low value stages of soil moisture at 30 days after seedling emergence,flower bug stage,and filling stage in the whole growth period in Hetao irrigation area.Therefore,according to the conclusion and the local watering habit,it designed field watering experiment at different time.Using the orthogonal analysis,the results showed that it is suitable for watering oil sunflower at 30 days after seedling emergence,flower bud,flowering stage and the edible sunflower at 30 days after seedling emergence,flower bud,flowering stage,filling stage.On the basis of different actual production condition,it provided different production suggestion for the development of the sunflower.

Key words: Hetao irrigation area, Sunflower, Watering period