洛阳地区是我省主要产棉地区之一。解放后,推广了一些行之有效的植棉技术,植棉水平有很大提高。但是,在指导棉花生产时,对怎样掌握“时宜”这个问题上,曾有过一些经验教训。譬如在确定棉花播种期方面,曾有过单纯以“节令”为准或以地温为准的作法。提出过“清明早,立夏迟,谷雨种棉最当时”、“谷雨前,好种棉”。也提出过“地温稳定在12℃以上”。这些提法虽不算错,但都不够完善,因为,每年同一节令的 Luoyang area is one of the major cotton producing areas in our province. After the liberation, some effective cotton planting techniques were popularized, and the cotton planting level has been greatly improved. However, there have been some lessons learned on how to grasp the “current time” when guiding cotton production. For example, in determining the sowing date of cotton, there has been a simple “seasonal order” or to geothermal prevail practices. Proposed “Qingming early, late summer, Guyu cotton most of the time”, “Guyu before a good variety of cotton.” Also proposed “ground temperature stability at 12 ℃ above.” Although these formulations are not wrong, but not perfect, because the same year a year