A modification to your English verse...

美酒飲教微醉後，好花看到半開時
A man knows a wine only at tipsy;
A flower becomes a true beauty only at half-blooming.

The following is a modification to your verse in which I have tried to make a less aggressive statement about the art of appreciation.

At tipsy a man knows a wine best;
At half-blooming a flower shows its true beauty.