Everyone gets all excited about warm temps. Last March was cold. A cold March is good if you have fruit trees. Keep em asleep as long as you can. Warm March forces them to wake up. Buds open. Then it is inevitable another cold shot will sneak in. Usually around the first of April an get down there maybe 19 or 20 and you have flowering trees. No fruit that year. Southern Iowa more susceptible than Northern Iowa to this. So,,a warm March is nice but menacing if you grow fruit.