Brooklyn did the too! And our trainer told us to do exactly what Karlin mentioned, and it worked like charm. We just took her across the street, to different patches of grass every morning (we had to get up a little earlier for a while too BTW, just to give her enough time...knowing she had to burst at some point!). Eventually, she would go anywhere. But yeah, I remember days where she would hold it almost all day because she wasn't "at home", poor thing, then would run outside so fast and pee for ages, like 3-4 times because she had so much in her! I guess the good thing is that she learned to hold it (but probably not for the right reasons!).
Also, every time I knew it was around the time where she would be busting for a pee and it wasn't first thing in the morning, I would just take a book (because frankly, she would just hold it til we got home if not) and go sit on a bench or in the grass and just wait, and wait and wait...until she peed! Then, when she did, I would give her a high reward treat (she only got roast chicken for potty training as this was a major winner for her and if she only got it when she peed, then she went right away). Anyway, it seems like a lot, but once Brooklyn "broke the seal" away from home once, it only took about a week for it to become common for her to go anywhere. She is only about 9 months now, so I am still doing the praising and party throwing when she goes outside of our house, just so she doesn't forget through adolescence. It is quite funny really, I feel like I have dried liver in the pocket of everything I own! Ha.