Sometimes more serious situations, after a bit of work, reach the sorry stage. When you get there, it’s okay to pull out the posies, though tulips or roses are probably a better idea.

When the aim is to apologize, only cut flowers will do.
Potted plants have many uses, saying you’re sorry isn’t one of them.
This is where all the fuss associated with cut flowers works to your advantage. You want the fuss. You want the gesture noted. In addition to the flowers, include a card.
Vase, no vase, it really doesn’t matter. In this instance, it really is the thought that counts.
After you’re forgiven, then she can decide what to do about water for the flowers.