Updated January 2015. The increased cost of health insurance is a central fact in any discussion of health policy and health delivery. As annual premiums edged beyond $16,800 for an average family, costs are blamed for rising uninsured and under-insurance..
Figure 1. Corn growth and temperature levels. Corn will germinate and grow slowly at about 50 F (10 C), but the average first spring planting dates across the U.S. usually begin when the average air temperatures reach 55 F (13 C) and soil temperature at seed depth is favorable for seedling growth.
Maps of Optimum Soil Temperatures for Planting Figure 1 shows the general distribution of when soil temperatures first reach a minimum temperature each season, based on average soil temperatures over the last 10 years. For example, much of the state reaches the 55Â°F soil temperature during the first to third week of April. Since field corn requires a minimum soil temperature of 55Ã¢ Â°F to germinate, the average earliest time to plant field corn would be in the second or third week of April. For other crops use Table 1 to determine the minimum soil temperatures required for germination and use Figure 1 to view the average time when a location reaches a given temperature. It is important to understand that the soil temperature maps in Figure 1 provide an average trend using data from the last 10 years to provide generalized results.