It's objective in that the aesthetic properties are present from the objective, anti-egoic state of mind. That perspective isn't perfectly universal, though. The data pass through our senses and our physical vantage point, so we see the flower from different angles, for example. And our background knowledge comes into play, despite our personal detachment from it, in that we objectify ourselves as we're having the aesthetic experience. We notice abstractly not just the flower, but the effects it's having on our senses and on our character and our memories. This is why aesthetic judgments differ even between experts, because the experience is generated by the objectified interaction between the external world and our individual minds. What's objective in it is the relatively selfless attitude with which we notice things without taking much personal interest in them.