How to ride Z2 in an hilly area?

Hello everybody, I would like to ask advices and suggestions about how to ride Z2 in an hilly area. I am living on top of an hill (250 mt), then I had to climb a bit at every training. Moreover, there are not real flat around, then it's hard to perform a real Z2 training. How to approach the hills then? I usually keep Z2 on flat or mild climbing and then SS on longer hills. Am I doing wrong?