It is that time of year when the trees are in bud, the frogs are horny and thoughts of getting the garden ready are at hand. I found this an interesting article that explains the differences and methodology used for each map. Most people are unaware except if they see it on the back of a pack of seeds.
https://fivethirtyeight.com/features/two-government-agencies-two-different-climate-maps/
https://fivethirtyeight.com/features/two-government-agencies-two-different-climate-maps/