As the God of Blight and Wheat Rust, Robigus does not receive divine honors. However, He does receive offerings to keep away from the crops. During the Robigalia, held on April 25, the Roman would sacrifice red dogs and sheep. In modern times, red wine is offered instead.
This is a form of sympathetic magic since the color of wheat rust is red. By giving red offerings to Robigus, He will be satisfied and leave the crops alone. Oberon Zell-Ravenheart defines sympathetic magic as “things that have affinity with each other influence and interact with each other over a distance,” according to. This means that everything is connected to everything else. Moreover, the offerings follow the Law of Similarity, as stated by Isaac Bonewits, of “like produces like and effect resembles its cause.”
Christianity adopted Robigalia and renamed it Rogation Day. During Rogation Mass, priests wore violet vestments. Then after prayer and fasting, the farmers would have their crops blessed.
“Spare Ceres’ grain Scabby Robigus, what You touch kills them. Do not harm the crops.” – Ovid.