4月份正值我国传统的清明和谷雨节气,本月日照加强,降雨增多,这是冬去春来后的明显变化,在我国黄河流域以北也能感到春天的到来,同时每天有效的日照时数从北纬20°左右地区,如海口、湛江、北海等地,至最北的48°左右地区,如佳木斯、齐齐哈尔、满州里、大庆等地均在13小时至13小时35分之间,有利于长日性花卉的花芽分化与发育。但在北方某 In April, when the traditional Qingming and Guyu secussions of our country were normalized, the sunshine this month strengthened and the rainfall increased. This is a clear change after winter and spring. The spring can also be felt to the north of the Yellow River basin in our country. At the same time, the daily effective sunshine hours From about 20 ° north latitude, such as Haikou, Zhanjiang, Beihai and other places to 48 ° north of the region, such as Jiamusi, Qiqihar, Manchuria, Daqing and other places are between 13 hours and 13 hours 35 minutes, there are Conducive to long-term flower bud differentiation and development. But somewhere in the north