双辽市建设乡杨国忠是一个种菜很有诀窍的老菜农。几年来他在露地生产蔬菜采取多茬套种方法，效益连年可观。去年，他又在２００ｍ２面积上，搞起了元葱套作大头菜，收益很是看好，每ｍ２效益可高达１５元。其技术环节是：１　合理安排生育期 第一茬元葱：头一年秋季９月初培育 Shuangliao City Construction Yang Guozhong is a kind of vegetable is a knack of veteran farmers. Over the past few years he was in the open field production of vegetables to take more stubble interplanting method, the benefits year after year considerable. Last year, he and again in 200m2 area, set up a green onion for kimchi, income is very optimistic about the benefits per m2 up to 15 yuan. The technical aspects are: 1 Reasonable arrangements for the first crop of growth period onion: the first year of autumn early September cultivation