Sending seeds to a house with a future or current grow is a little risky. However, setting up a PO Box under an assumed name is very difficult; particularly after 9/11. You need several forms of ID for PO boxes and unless you have some hook-up's for fake ID's, you're probably not going to get one.
Besides, I think the risks involved with setting up a PO Box with a fake name would be greater than the risks of having seeds sent to your home.
Still, even a PO Box under your name is safer then getting stuff sent to your house. If you do get a PO Box, make sure and get it somewhere that has a lot of volume. Small "mom and pop" mail drops are no good. If you get a Green Tape Monster, that might raise an eyebrow or two and cause suspicion. Then you might have something to worry about. The higher the volume of mail in the mailboxes, the less people are going to pay attention to individual pieces of mail IMO.