It means that you can get 2 crops per year in. That you can grow just about anything but tropicals. And since you are at 7, instead of 8, you get some of the best of both worlds.
You can plant stuff that normally only grows way up north and yet, you can also grow some stuff that is decidely warm blooded.
If you try blue berries, try southern blue berries because if you hit an extremely hot summer, the northern ones can die from heat.
Oh, and don't forget to check out stuff that you "thought" were only for tropical areas. You can grow some cold-hardy bananas in your area.