Soil temperature and air temperature are very important for your planting decision. Here are guidelines from the Alabama Cooperative Extension… http://www.aces.edu/pubs/docs/A/ANR-1061/ANR-1061.pdf
The general relationship between days until seedling emergence and percent germination is inverse. What this means is that considering the optimal temperature for planting seeds, you will want to tend to plant too early instead of too late: the seeds will germinate best when the temperature is ideal, and trusting them to the ground when you have few birds or other creatures who will dig up the seeds is intelligent. Planting extra as precaution against this predation is also advisable.
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