He was one of the most famous Viennese flower painters of the first half of the 19th century. He studied flower painting at the Vienna Academy from 1797 to 1805. From 1807 to 1811 he was the assistant to his teacher, Johann Baptist Dreschler, at the Academy's flower painting class. Wegmayr succeeded Dreschler as professor of flower painting in 1812, a position he held until 1850.