Planting should not occur before soil temperatures are near 50° F for corn with a positive weather outlook. At 50° F corn will take approximately 25 days to emerge. At 55-60° F corn will take 10-14 days to emerge. At 65-70° F corn only takes five to eight days to emerge . How long a seed can last in the soil and remain viable depends on temperature, moisture, and pests.
Oxygen
Oxygen is necessary as respiration increases during the germination process. Lack of oxygen is rarely a concern except for flooded soil conditions, which offer a significantly lower level of oxygen to the respiring seed and can kill the seed if conditions persist.
