April 15th is Fordicidia, a festival to Tellus (Terra) held during the Cerealia Festival. the Fordicidia was a festival of fertility, that pertained to farming and animal husbandry. It involved the sacrifice of a pregnant cow to Tellus, the ancient Roman goddess of the Earth, in proximity to the festival of Ceres on April 19. Of course today any ritual or festival that requires sacrifice should be a symbolic jester of tribute to the gods.
On the Roman religious calendar, the month of April (Aprilis) was in general preoccupied with deities who were female or ambiguous in gender, opening with the Feast of Venus on the Kalends. Several other festivals pertaining to farm life were held in April: the Parilia, a feast of shepherds, on April 21; the Robigalia on April 25, to protect crops from blight; and the Vinalia, one of the two wine festivals on the calendar, at the end of the month. Of these, the Fordicidia and Robigalia are likely to have been of greatest antiquity.
Tellus was the name of the original earth goddess in the religious practices of the Republic or earlier. The attributes of Tellus were the cornucopia, or bunches of flowers or fruit. Festivals celebrated for Tellus were mainly concerned with agriculture and often connected with Ceres. Tellus was felt to be present during rites of passage, either implicitly, or invoked. She was perhaps involved in the ceremonies attending the birth of a child, as the newborn was placed on the ground immediately after coming into the world. Tellus was also invoked at Roman weddings.
Give thanks to the Mother Earth.
Give thanks to the Father Sun.
Give thanks to the plants in the garden,
Where the Mother and Father are One.