Everyone is different. Give the gift according to your feelings, expressions as well as whom you are giving the gift.
For some women, flowers would be perfect. For others something more practical. And others still something extraggent.
For me, for example, I prefer something thoughtful - if for instance you give 7 roses - because you have been dating for seven months - there is thought in there - add certain colors for a particular reason or even a different type of flower for another reason and you increase the thoughtfulness.
Think of who you are giving the gift too. What would she like/enjoy the most. It isn't always the price - you are already a step up from other men (in my opinion) as you have a reason for choosing flowers - you could also write a little something that expresses why you choose flowers.