Originally Posted by Richard

Mauro,
As we discussed before, there is a problem with the USDA cold hardiness zones. For some people, "9a" is about 10 nights a year of temperatures dropping from 35 F to 25 F and otherwise daytime temperatures above 40 F. However, for a lot of people "9a" is daytime temperatures in the high 30's and nighttime temperatures in the low 20's. Obviously, fruiting bananas grown in the 1st example are not likely to survive in the 2nd.