Offering flowers

I offered some roses yesterday, that I got from my dad, to lady aphrodite. I see it as a decent offering, since its meaningful to me and it was given with parental love. But im not sure if I should leave it be, or switch water every day, so it doesn't welt and all that. For normal flowers that are just for decoration, I switch water every day so it stays as fresh as possible and as long as it can last. But now idk if I should leave it be, because its an offering, or should I still switch water.