I know each of us has a different idea as when to apply a Pre-Em. I wait until ground temp is a stable 55. Others wait "When the forsythia is in bloom" or "During the last of February to March 15" and so on and on. But for the really scientific endowed minds: What leads you to when you apply your pre-em? For the coast of SC the stable 55 is generally about March 10th or so. Just some food for thought.