The [series of] book[s] Chemdas HaYayamimmim contains a broad range of topics (philosophy, morality, custom, law), based on the special days of the year. Along the way, in several places it discusses significances of specific months, including Nisan.
Edit: Please note that, despite the disclaimer on the title page, some information is known about its author and the author was a Shabtai Tz'vi adherent. Views based on that influence are expressed in Chemdas Yamim.