One thing in particular I have learned this season about Bermuda: When mowed at lower heights (1.5" or less) the turf retains color MUCH longer. I have lawns located on the same street that are maintained at various heights. The higher cut lawns (2" and up) were the first ones to go dormant from the frost. The reel cut lawns have retained color as much as 1 month longer for example. My theory behind this is that the lower cut turf retains warmth as it is closer to the soil. The higher cut turf is more exposed to the colder air, so it stops photosynthesis much sooner. Certain areas also have microclimates that effect dormancy, but this rule seems to hold true.