Personally, I'm anti-roses. I've never given any girl I've been seeing roses. They're just too cliche, in my opinion. Go for lillies, carnations or dasies, they're always a hit.
Agreed. And roses are way overpriced.
There is some truth to the sentiment that if you aim low now, you won't have to worry about outdoing yourself for several years down the road. If you start with a bang and drop $200 on her after 3 months, imagine what she'll want after a few years.

But, of course, you can't get away with not getting her something really small, can you?
I would recommend try doing something that is not too cliche. Instead of taking her out for dinner, make her dinner. Find out what her favorite is and try your best. Some guys are great at cooking, others have never done it. Sometimes women respond to good intentions, sometimes it doesn't mean anything. If the lady you're with is worth pursuing in the future, she should hopefully respond favorably to your efforts, regardless of the outcome.