The name Aprilis was already an argument in ancient Rome. The scholar Varro derived it from aperire, to open, because April is when the buds of spring open, while Ovid, dedicating the fourth book of the Fasti to Venus, derived it from Aphrodite, the goddess's Greek name, and modern scholarship has added a third candidate in the Etruscan form Apru. No ancient authority settled the question and no modern one has either, which makes April the first of three months in the Roman spring whose names were contested by the very poets who explained them.
Whatever its etymology, Roman April behaved like Venus's month at its opening, with the Veneralia on the first day, and like a farmer's month for the rest: the Parilia of the twenty first, the shepherds' purification festival, doubled as the traditional birthday of Rome itself, and the Cerialia honoured Ceres, goddess of the growing grain, with games in the middle of the month. The Floralia, opening on the twenty eighth of April and running into May, greeted the flowering of the year with a licence that later moralists found scandalous, and the Robigalia of the twenty fifth asked the spirit of grain rust to spare the crops, a procession whose route and date the Christian greater litanies later inherited.
April's religious character has stayed vernal ever since: the month of opening buds became, in the Christian centuries, the month that most often holds the open tomb of Easter morning.
Sources FastiOvid with Religions of Rome, Volume 1: A HistoryMary Beard, John North and Simon Price