section_path: Cultivation/Conditions
section_name: Conditions
paragraph_text: Conditions
  
  Cultivation is successful in climates with hot summers, with optimum growing conditions in mean temperatures of 20 to 30 °C (70 to 85 °F); temperatures of below 20 °C (70 °F) and over 40 °C (105 °F) stunt growth significantly. They can grow in a wide range of soils, with optimum growth in moist alluvial soils with good organic content. Soybeans, like most legumes, perform nitrogen fixation by establishing a symbiotic relationship with the bacterium Bradyrhizobium japonicum (syn. Rhizobium japonicum; Jordan 1982). This ability to fix nitrogen allows farmers to reduce nitrogen fertilizer use and increase yields when growing other crops in rotation with soy. There may be some trade-offs, however, in the long-term abundance of organic material in soils where soy and other crops (for example, corn) are grown in rotation. For best results, though, an inoculum of the correct strain of bacteria should be mixed with the soybean (or any legume) seed before planting. Modern crop cultivars generally reach a height of around 1 m (3 ft), and take 80–120 days from sowing to harvesting.