What is the ruling on writing amorous poems for one's wife?

It is permissible for a husband to write romantic poems for his wife, including expressing his love and mentioning her virtues, provided that the romantic verses are exclusively for her and no one else besides the wife sees them. Otherwise, it would be contrary to murūʾah (chivalry/propriety). It is forbidden to write tashabbub (amatory poetry) about a specific forbidden woman or an unbearded youth, and it is forbidden to mention lewdly suggestive descriptions of an unrelated woman. As for writing tashabbub about one's wife, it is permissible unless he describes her private parts or mentions what should be concealed, as that would diminish murūʾah.