Man I highly recommend leaving a new crop for one month. You put all that work/risk/investment into it and you are leaving at the most critical time? I hate to say it, but I would really think about the timing when you start the next grow. As for your specific question.. only thing you can do is chop it and leave it in a dark, well ventilated space. However, if you have huge buds then they might mold. It will be extremely dry when you get back so your gunna have to bust out some lemon/orange peels to moisten it up.